Adaptive framing of sustainability in CEO letters

Purpose – This study provides insights into the external powers that can influence business leaders ’ communication on sustainability. It shows how the socio-political context manifested in national and transnationalpolicies,regulationsandothersocio-politicaleventscaninfluencetheCEOtalkaboutsustainability. Design/methodology/approach – This study adopts an interpretative and qualitative method of analysis using the lenses of the theoretical concepts of framing and legitimacy, analysing CEOs ’ letters from 10 multinational industrial companies based in Sweden, over the period of 2008 – 2019. Findings – The results show that various discourses of sustainability, emerging from policies and regulatory initiatives, socio-political eventsand civil society activism,are reflected in the ways CEOs frame sustainability over time. This article reveals that CEOs not only lead the discourse of profitable sustainability, but they also slowly adapt their sustainability talk to other discourses led by the policymakers, regulators and civil society. This pattern of a slow adaptation is especially visible in a period characterised by increased discourses of climate urgency and regulations related to social and environmental sustainability. Research limitations/implications – The theoretical frame is built by integrating the concepts of legitimacy and framing. Appreciating dynamic notions of legitimacy and framing, the study suggests a novel view of reporting as a film series, presenting many frames of sustainability over time. It helps the study to conceptualise CEOframingofsustainabilityas adaptiveframing.Thisstudysuggestsusingadynamicnotion of adaptive framing in future longitudinal studies of corporate-and accounting communication. Practical implications – The results show that policymakers, regulators and civil society, through their initiatives, influence the CEOs ’ framing of sustainability. It is thus important for regulators to substantiate sustainability-related discourses and develop conceptual tools and language of social and environmental sustainability that can lead CEO framing more effectively. Originality/value – The study engages with Goffman ’ s notion of dynamic framing. Dynamic framing suggests a novel view of reporting as a film series, presenting many frames of sustainability over time and conceptualises CEO framing of sustainability as adaptive framing.


Introduction
In recent years, societal pressure on companies to transform into sustainable businesses is increasing (Laine et al., 2020;Arvidsson, 2019). There is a growing expectation among stakeholders to receive reliable accounts from companies, informing the public about their progress on environmental and social dimensions of sustainability (Khan et al., 2020). We witness an increasing interest and awareness from stakeholders regarding how sustainability is addressed by corporate management (Arvidsson and Dumay, 2022;Thijssens et al., 2015) and what the environmental and social impacts of their operations are (Andersson and Arvidsson, 2022;Fernandez-Feijoo et al., 2014). Moreover, a growing critique addressing the lack of stakeholders' inclusiveness and authentic integration of sustainability in corporate management and operations (Perkiss et al., 2020) increased pressure from the civil society, demanding an urgent transformation of the business-as-usual. Various protests and debates driven by climate-and human rights activists ostensibly influence policymakers and regulators worldwide to develop a multitude of national and transnational policies, regulations and initiatives (e.g. NFRD/CSRD; TCFD; the EU Taxonomy), promoting business innovations (Hysing and Olsson, 2017) in line with the agenda for sustainable development [1]. CEOs are corporate leaders that have (the) power to influence the development on the business arena, but also on the political arena. The words of CEOs have a potential power to shape the perceptions of stakeholders in society , and, moreover, create an ideology, which can reinforce some worldviews -and weaken others (M€ akel€ a and Laine, 2011). At the same time, CEOs can be viewed as actors, whose rhetoric is shaped by society, and, from this perspective, CEOs' increasing talk of sustainability becomes a response to socio-political discourses of sustainability (Milne et al., 2009). Large industrial companies often have a wide international presence, being influenced by national and transnational socio-political context (Rondinelli and Berry, 2000). Therefore, we argue that CEOs of these companies are not only powerful leaders, promoting the ideology of economic sustainability of business (M€ akel€ a and Laine, 2011), but they are also adapting their ideas and rhetoric to the socio-political discourses evolving over time. The national and transnational policies, regulations and socio-political events of the last decade constitute the socio-political context, in which the multifaceted discourses of sustainability evolved. As a result, discourses of sustainability have become strongly influential in society . This influence has also been mirrored in the way corporate leaders address sustainability in their speeches and letters (Arvidsson, 2023;Albertini, 2021).
It is relevant to explore CEO letters as a medium where corporate leaders communicate their views and perspectives on sustainability. Previous interpretive research of corporate sustainability talk argues that business leaders promote inclusion of sustainability into corporate business agenda by using a pragmatic win-win approach and responding to market demands (Gray, 2010;Laine, 2010;Milne et al., 2009;M€ akel€ a and Laine, 2011;Tregidga et al., 2014). There is, however, a lack of studies exploring the CEOs' sustainability talk as shaped by the socio-political context, and not limited to a focus on the profit-driven perspective of companies (Tregidga et al., 2018). Already in 2009, Milne et al. (2009) argued for the need of studies of how organisations talk and write about sustainability in the "ongoing discursive and ideological contest over environment and development" (p. 1220). In the context of Agenda 2030, this call gets highly relevant. Employing an interpretive approach to textual analysis (Wang, 2017;Laine, 2010), this study contributes to the above-mentioned research by examining the influence of policies, regulations and socio-political events, including civil society activism, on the CEOs' sustainability talk. Therefore, we examine the CEOs' talk of sustainability as an exercise of adaptation to the socio-political discourses evolving over time.
To contribute the existing research, we integrate two theoretical concepts -legitimacy (Meyer and Rowan, 1977;Suchman, 1995) and framing (Goffman, 1974). Rooted in institutional theory, the legitimacy-perspective views organisations as strongly influenced by their surrounding socio-political context. To gain legitimacy and ultimately survive, organisations strive to be perceived as conforming with institutionalised concepts and structures over time (Meyer and Rowan, 1977). Thus, we view the sustainability talk in CEO letters as adaptive to institutionalised conceptualisations of sustainability in the society. Another theoretical concept used in the analysis is framing (Goffman, 1974). We engage with Goffman's notion of dynamic (not static) frames, inspired by drama and film. Dynamic framing enables us to see the annually communicated CEO letters as a series of film frames, presenting many pictures (frames) of sustainability over time. We argue that the film directors (the CEOs or other managers) are the framers, who carry out a performance to influence their stakeholders' perceptions of the company. In search of legitimacy, the CEOs develop framing of sustainability aligned with the dynamically evolving sustainability discourses, represented by national and transnational policies, regulations and socio-political events related to sustainability. We argue that the CEOs do this in order to adapt to these dynamically evolving discourses and to persuade the audience (different stakeholders) that their corporate values are congruent with the societal ones in a particular time and space. Thus, this study addresses the following research question: RQ1. How is sustainability being framed and adapted to national and transnational sustainability discourses over time?
Grounded in the comprehensive interpretative paradigm, this study performs a textual analysis of CEO letters of 10 multinational industrial companies, based in Sweden, over the period 2008-2019. Multinational industrial companies are typically organisations with different types of stakeholders and significant environmental and social impacts (Rondinelli and Berry, 2000), which makes the case relevant in the context of sustainable development.

Theoretical foundations 2.1 CEOs' talk of sustainabilityprevious research
In critical accounting research, narrative sustainability reporting, performed by corporate leaders, is often viewed as a means for gaining and re-gaining legitimacy, conveying the discourse of reconciliation between economic growth and sustainable development, rather than a means of accountability for vital environmental and social issues (Milne et al., 2009;Beelitz and Markl-Davies, 2012). CEO letters are rich textual manifestations of the business voice, where such a reconciliation discourse is being performed as a way to align the shareholders' interests with the stakeholders' interests (Milne et al., 2009). Suggesting that CEOs are influential leaders on the business-and political arenas, Craig and Amernic (2004) put forward that the words of CEOs do not only influence perceptions of stakeholders, but also promote ideology. M€ akel€ a and Laine (2011, p. 229) develop this argument further and, inspired by Tinker and Neimark (1987), suggest viewing the CEO letters as "ideological weapons" that can reinforce some worldviews and weaken others. Evidently, CEOs' talk has a potential power to influence others. However, as rich evidence of Sustainability framing in CEO letters critical accounting research shows, this power has mainly been used by the corporate leaders to sustain the ideological position of the business gate keepers, claiming that there is no conflict between business development and sustainable development, optimistically rationalising these two as a "win-win" (Gray, 2010;Tregidga et al., 2014). Furthermore, corporate accounts of sustainability conveyed in corporate annual reports including CEO letters, has been criticised for being a mere greenwashing activity (Arvidsson, 2019), by using a manipulative rhetoric (Collison, 2003) that creates a distorted picture of corporate business, projecting a fake change towards sustainable business conduct (Beelitz and Merkl-Davies, 2012;Laine, 2010). At the same time, corporate rhetoric can also be viewed as a response to socio-political context (Milne et al., 2009;Scott, 2001). Large companies often have a wide international presence, being influenced by national and transnational socio-political events and discourses (Rondinelli and Berry, 2000;Laine, 2009). Therefore, the powerful leaders (CEOs) are promoting ideology related to sustainability by adapting their ideas and rhetoric to the socio-political discourses evolving over time. Here, sustainability is seen as a dynamic concept situated in local, temporal and political domains, influencing its perception over time (Hallin et al., 2020). Without being situated, sustainability is an empty category of which individuals and organisations fill with a polyphony of meanings (Busco et al., 2018). Thus, it is a discursive concept (Busco et al., 2018), moving across a variety of legitimate discursive spaces (Tregidga et al., 2018).
In recent decade, political and societal awareness of the critical importance of environmental and social sustainability has gradually increased and became urgent, especially since the launch of Agenda 2030 and Paris Agreement in 2015. This awareness has resulted in many stakeholders and activists questioning existing businesses. This has further increased pressure on politicians to introduce new regulatory initiatives and frameworks for promoting corporate transformation towards sustainability. For example, in the accounting field, there has been a shift from primarily voluntary initiatives towards legislative and normative ones, focusing on the social and environmental dimensions of sustainability (T2). In the case study of a large Finish chemical company, Laine (2009) illustrated how local sociopolitical context in Finland shaped the development of the company's sustainability reporting practice by imposing various institutional pressures over time. Furthermore, Millar and Searcy (2020) showed how civil society and science can influence sustainability reporting practice. We believe that studying this perspective is important, because it crystallises the power of policies, regulations and socio-political events related to sustainability to change corporate rhetoric. Previous research has not given enough attention to the perspective of how the business leaders (the CEOs) adapt their frames to socio-political context changing over time. Understanding of external to organisations enabling forces for sustainable development is still limited and much needed in the accounting research (Bebbington and Unerman, 2020). Our study addresses this call by focusing on how policymakers, regulators and civil society influence the CEOs' adaptive framing of sustainability over time.
2.2 Adaptive framing to gain/maintain legitimacy over time Institutional theory and specifically the concept of legitimacy provides the theoretical foundation on which this study rests. Institutionalist researchers have long conceptualised the relationships between organisational practices and the socio-political context in which organisations operate (Vermeulen et al., 2016). Organisational practices of reporting and communications are strongly influenced by continuously changing societal norms and values manifested in the complex environment (Martins et al., 2020). Therefore, in this complex and changing context, organisations need to continuously adapt to these norms and values in order to stay legitimate in the society (Martins et al., 2020).
Our theoretical frame(work) is built by integrating the concepts of legitimacy (Meyer and Rowan, 1977;Suchman, 1995) and framing (Goffman, 1974). According to Meyer and Rowan (1977) organisations strive to be perceived as conforming with the institutionalised concepts and structures to survive. A perception of being the one conforming with the "myths" of modern society makes an organisation acceptable, thus legitimate in the modern society. In their strive for legitimacy, organisations often "dress up" in the frames of existing institutionalised concepts and structures. These institutionalised concepts are being aligned with the cultural context, norms and beliefs in society, surrounding organisation; and they also change over time along with the socio-political changes in society (Scott, 2001). It implies that legitimacy is not a stable resource given to the organisation due to its conformity with the norms, but it is a dynamic process of communication between the organisation and its stakeholders (Suchman, 1995).
Being dynamic, legitimacy is thus moving in line with the social norms and beliefs and is time-and place-specific (Suchman, 1995, p. 574). As societal expectations are changing over time, organisations need to communicate to their stakeholders about their values and beliefs, changing in line with the society. To do this, organisations use adaptive framing as a form of response to the stakeholders' demands and expectations to gain or maintain legitimacy. Organisations often use verbal and written accounts to respond to these demands and expectations in the surrounding complex environment (Martins et al., 2020). Accounting communication (Merkl-Davies and Brennan, 2017) and, particularly, CEO letters in corporate reports (Amernic et al., 2010;M€ akel€ a and Laine, 2011;Jon€ all and Rimmel, 2010;Arvidsson, 2023) are important communication channels used for managing such perceptions. Being time and space-specific, the business leaders' communication seeks to project an alignment between the stakeholders' and companies' interests (Milne et al., 2009), adapting their talk to the socio-political discourses that mirror societal norms and beliefs over time.
For example, in recent decades discourses of sustainability have become strongly influential . Discourses of sustainability, driven by policymakers, regulators and activists represent societal values. Sustainability-related debates and protests driven by climate and human rights activists undermine trust to businesses in the society (Ferguson et al., 2016;Perkiss et al., 2020). In this context, corporate leaders ostensibly respond to the socio-political developments by adapting their framing of sustainability in CEO letters. Thus, we see CEO letters of large-listed companies as a medium where corporate leaders frame and reframe sustainability over time. In this way, they adapt to national and transnational discourses of sustainability and persuade stakeholders that their values are congruent with the societal ones in a particular time and space.
Framing, as it is conceptualised by Goffman (1974), becomes useful for the analysis of this phenomenon. Erving Goffman's work is imbued with a dramaturgical perspective on social life, suggesting that in everyday life, people, like being on the scene, are using language and dresses as means for "presentation of self", to shape perceptions of others, a phenomenon called impression management (Goffman, 1959). Within this dramaturgical perspective, Goffman (1974) in his later work developed Bateson's (1955) concept of the static frame of a picture further by ". . . rendering the notion of frame dynamic by the insight taken from the films, in which a frame is one of many pictures, but where framing becomes a habit and a sign of style of the photographer or the director" that changes over time (Czarniawska, 2006(Czarniawska, , p. 1667).
Goffman's earlier work (Goffman, 1959) has been used in accounting research for analysing corporate communication from the impression management perspective (Beelitz and Markl-Davies, 2012;Perkiss et al., 2020). Prior accounting studies tend to use concept of the frame of a picture in a static meaning, as coined by Bateson (1955) and Goffman's earlier work (Goffman, 1959). In this study, we adopt Goffman's later notion of frame dynamic inspired by drama and film (Goffman, 1974(Goffman, , 1981. In line with this approach to framing, we Sustainability framing in CEO letters see annually communicated CEO letters as a film series, presenting many pictures (frames) of sustainability over time. We argue that the difference between dynamic and adaptive framing is that adaptive framing occurs in response to specific discourses and events for the purpose of legitimising the organisation over time. Here, we see the directors, who are the framers, carrying out a performance, to influence their audience perception of the company.
In the search of legitimacy, the CEOs develop framing aligned with dynamically evolving sustainability discourses, represented by national and transnational policies and regulations, socio-political events and civil society activism. Each episode contains a set of frames including various themes reflecting socio-political discourses that together constitute framing.
To summarise, the concept of legitimacy explains why CEO conceptualisations of sustainability are adapted to the norms and believes in the society and is dynamically changing over time. Framing complements the legitimacy concept by providing insights into the discourses, shaping the frames of sustainability over time. Thus, framing helps researcher to establish connection between the CEO's conceptualisations of sustainability and specific policies, regulations and other events in the society over time. By complementing each other, the two concepts together build the novel theoretical notion of adaptive framing.

Research method
The CEO letters are analysed by using qualitative textual analysis anchored in the interpretive paradigm. Interpretative textual analysis is a qualitative research method with a long history (Laine, 2010;Milne, 2004;Tregidga and Milne, 2006;Wang, 2017). It is widely used by sociologists and narratologists (Czarniawska, 1997) in the analysis of themes and discourses of texts. In this study, we identify the themes in the letters and connect them to the discourses of the surrounding national and transnational socio-political context. This connection allows us to uncover how the framing of sustainability is embedded in a sociopolitical context (Ogden, 2002). For the analysis of the themes and discourses, and their patterns of diffusion over time, we perform manual interpretive analysis, complemented by NVivo (Perkiss et al., 2020).
To examine how CEO talk of sustainability has developed, an interpretative textual approach (Wang, 2017;Laine, 2010) is applied to sustainability talk in CEO letters. Previous research shows that the CEO letter is the mostly read section of the annual report Amernic et al., 2007Amernic et al., , 2010M€ akel€ a and Laine, 2011). It is a signed letter addressed to the company's stakeholders where the CEO presents business events, strategic ambitions and important topics guiding the management team's agenda. We are aware of that the CEOs may not have structured and written the CEO letters themselves. Most likely, it is a co-creation by several actors. However, the letter is signed by the CEO and is therefore regarded as CEOs' talk representing the business voice.

Construction of the study's data-set
To examine how CEOs frame sustainability over time, we collected CEO letters of the large Swedish companies from industrial sector (GICS industry Industrial), listed at Nasdaq Stockholm Stock Exchange under NasdaqOMXS30 index (T1). In total, 120 CEO letters from the annual reports 2008-2012 were analysed.
The selected 10 industrial companies represent 37% of the NasdaqOMXS30 index (see Table 1). The choice to focus on the industrial sector is motivated by its significant impact on environmental (e.g. emissions, resource consumption), social (e.g. global trade, human rights, corruption) and economic dimensions (e.g. growth, profits). All selected companies have a wide global presence and have significant national and international impact related social and environmental issues (T1). Gaining legitimacy is vital for organisations that have multiple and complex goals and whose outputs are difficult to measure. Multinational industrial companies are an example of such organisations, as their international presence as well as pressures coming from multiple stakeholders lead to a complex and multifaceted set of goals and outcomes, especially those related to environmental and social dimensions (Rondinelli and Berry, 2000). The data set represents the business voices of 10 multinational enterprises (MNEs) based in Sweden and largely operating on the global arena. The choice of the ten largest industrial companies is motivated by their position as trendsetters (Stiller and Daub, 2007).
We know from previous research that both international (Adams et al., 1998;Levi-Faur, 2005) and national (Hall and Soskice, 2001) socio-political events influence the discourses of the largest companies. The Swedish origin of the studied companies is worth acknowledging since Swedish companies are often the front-runners in sustainability disclosures (Cahan et al., 2016;KPMG, 2019), and perceived to have established business ethics practices (Singh et al., 2011). In addition, the chosen companies also represent MNEs with a strong global presence, thus influenced by national and transnational socio-political context.
A scarce longitudinal focus in sustainability research is often emphasised as a shortcoming (Golob et al., 2013). To analyse the development of sustainability talk in the CEO letters influenced by the national and transnational socio-political context, we study a 12-year period (2008-2019), characterised of a variety of policies, regulations and sociopolitical events, related to sustainability. This approach is also in line with Goffman (1974) concept of the framing dynamics over time. The choice of 2008 as the starting year is motivated by the financial crises resulting in a shift towards increased importance of nonfinancial information. This shift resulted in policies and regulations and strong social and political engagement in sustainable development (Monciardini, 2016). CEO letters from the financial year 2019 were the latest available at the time of data collection. In the analysis,  Goffman (1974Goffman ( , 1981, we divided the studied timeline into three seasons of a film series: 2008-2011 (season 1), 2012-2015 (season 2) and 2016-2019 (season 3).

Analysing procedures
There is an ongoing debate in the sustainability literature considering which methods should be used to analyse sustainability disclosures (Chauvey et al., 2015). Hughes et al. (2001) argue that an analysis should focus on whether disclosures are quantitative, descriptive, vague or immaterial. Furthermore, Thomson and Bebbington (2005, p. 529) urge researchers analysing corporate reporting content to move "towards a more qualitative understanding of what reporters are actually saying (both explicitly and implicitly)", suggesting that "a more careful and sophisticated reading of accounts is necessary". In this study, we follow the latter approach and adopt a comprehensive interpretative research paradigm by using a perspective of discourse analysis (Czarniawska, 1997), focusing on what is actually said and why. From this perspective, we interpret the content of the CEO letters by relating it to the policy, regulations and socio-political events concerning sustainability in businesses and capital markets over time. This approach enables us to explain how the framing of sustainability by corporate leaders is embedded in a socio-political context (Ogden, 2002). Like Laine (2010) emphasises, studies that apply a comprehensive interpretive paradigm require numerous readings and re-readings paired with an interpretative analysis of themes, perspectives and developments in the text. Ultimately, it is a critical investigation of the CEO letters, how the sustainability talk is framed and developed over time. In our analysis, the focus is on identifying themes and dominating discourses in the CEO letters of the studied three seasons of film series produced by the CEO during 2008-2019. Table 2 illustrates the study's timeline and overviews the seasons, national and transnational policies, regulations and socio-political events occurring during this period (detailed in section 5). We identified and included significant national and transnational policies and regulations related to sustainability in business (Table 2). Furthermore, by using the Swedish database Mediearkivet, we identified other socio-political events that during the studied period received significant attention in media. The authors of this paper are actively involved in several national and international networks of policymakers, regulators and NGOs addressing sustainability issues, which was helpful in the process of mapping significant policies, regulations and other events.
The analysing procedure involved three stages. In the first stage, the focus was on in-depth reading of each CEO letter (the English version) by each of the authors. To make sure that we perform the analysis in a consistent way, we, first, read the letters of two companies for the years 2008, 2013 and 2019. We discussed all our observations together to make sure that the coding of empirical observations was performed in a coherent way. Subjectivity is present in all studies using interpretative analysis of text (Laine, 2010). Therefore, independent analysis and regular discussions and comparisons of the outcomes was a way to deal with the potential problem of ambiguity in the interpretation process. Next, all the letters were read in chronological order for each company by each of the two authors. All the observations were, first, documented in form of notes and mark-ups directly in a PDF version of each CEO letter. Thereafter, the mark-ups and notes were discussed and a joint PDF version of each CEO letter analysis was finalised.
In the second stage, all marked-up passages were carefully examined. Now the focus was to structure, interpret and code the insights that each passage included into thematic categories. This step included going back to the original annual reports to see where in the annual report the CEO letter was placed and what other highlighted themes in the content surrounding CEO letter might be of importance. At this stage, patterns of framing for each of the timeline's three seasons started emerging from the structured material. Simultaneously, we started developing the empirical storyline for presentation of the results, divided in the three seasons of the film series produced by the CEOs. The identified thematic categories in the CEO letters are presented in Table 3 in connection to seasons where these were identified.
In the third stage, the focus was on identifying the relation between socio-political context and the development of framing (Goffman, 1974(Goffman, , 1981 of sustainability in CEO letters over time. At this stage we engaged with national and transnational policies, regulations and socio-political events related to sustainability to understand and explain their influence on framing. In this process, we had close attention to their intended outcomes to establish a link between (1) the discourse of articulated intentions by policymakers, regulators and civil society activists and (2) the themes, identified as adapted frames in CEO letters over the studied seasons. These linkages are detailed in Tables 4-6, including specification of how many companies are using these themes in CEO letters, and how certain themes appear, increase, decrease or disappear over time.

Identified thematic categories
Time period (seasons) Triple bottom line (environmental, social, economic) 1,2 and 3 Sustainability(environmental) performance 1,2 and 3 Corruption, anti-corruption 1,2 and 3 Climate change 1,2 and 3 Environmental products and services from resource efficiency perspective (win-win) 1,2 and 3 Long-term perspective of growth 1,2 and 3 Code of conduct (business code) 2 and 3 Responsibility 2 and 3 Sustainable innovation 3 Integration, integrated 2 and 3 Value creation 2 and 3 Sustainable value and/or growth 2 and 3 GRI 2 Impact (economic, environmental and social) 2 and 3 Sustainability performance 2 and 3 Policies and risks related to sustainability 2 and 3 Stakeholders in addition to shareholders 2 and 3 Diversity 2 and 3 Paris agreement 2 and 3 Transformation/transition 2 and 3 Sustainability Development Goals (continued ) While in the manual interpretive analysis we focus on identifying and analysing the themes and discourses used in each CEO letter, the limitation of this approach is that researcher cannot look at all CEO letters and all seasons at the same time. Here, NVivo is helpful to grasp the big trends of diffusion of various themes and discourses in all studied letters over time. Therefore, we complemented our interpretive analysis with a number of textual NVivo searches. We used the function "explore" > "text search" and made different queries (single or combined words) applied to all companies' CEO letters in each season. The results of this search illustrated the number of paragraphs and reports where the searched words or expressions were used. Comparing search results over three seasons allowed us to see the general trends, where some themes and discourses were increasing or decreasing over time, supporting our interpretive story of framing. Nevertheless, by only using NVivo it would not be possible to identify all the themes and discourses used in the CEOs' sustainability talk. Thus, we argue for the importance of engaging with the comprehensive interpretive paradigm and perform the manual assessment of the text in relation to the socio-political context, and only use NVivo as a complementary procedure.

Empirical results: adaptive framing of sustainability by CEOs
We structure our presentation of results in three sub-sections, focusing on each of the three seasons: 2008-2011, 2012-2015 and 2016-2019. We see the letters of the studied period as a film series (Czarniawska, 2006), directed by CEOs, who adapt sustainability talk to the changing socio-political discourses over time. We link thematic categories in the letters to the discourses emerging from national and transnational policies, regulations and socio-political events (Tables 4-6, henceforth T4-6). Throughout the seasons, we include quotes from the CEO letters to provide illustrations of CEOs' adaptive framing of sustainability and relate our findings to previous research.

The first season (2008-2011): framing shareholders' expectations after the financial crisis
The first season starts with the global financial crisis, influencing many businesses in the world, including our industrial companies. During that time, a story about continuously improving financial performance was impossible for many companies to tell. Instead, the CEOs framed the letters by a dominating environmental perspective, where the focus was on the potentially reduced environmental impact as a future result of ongoing resource efficiency, development of new environmental products. The environmental perspective has been articulated during and after the financial crisis to ensure long-term market leadership, resulting (hopefully) in growing sales and future returns. Our results show that the discourses of transnational and national regulatory initiatives, as well as of socio-political events between 2008 and 2011 influenced the CEO talk but to various extent. For example, while the financial crises influenced almost all the industrial companies to frame their talk from a long-term perspective of growth (10/10) and an increased focus on resource efficient environmental products and services (9/10), the ICC Rules on combating corruption, a transnational regulation from 2011, only influenced 2 of 10 studied CEO letters. Below, we present and discuss the empirical material by following identified categories of the CEO framing. The connection between national and transnational socio-political discourses and CEO adaptive framing is also visualised in Table 4. The dominating focus on environmental perspective reflects an emerging discourse of climate change, which started diffusing on a global scale after Al Gore released a documentary An Inconvenient Truth in 2006 followed by the Nobel prize 2007 awarded to the Intergovernmental Panel on Climate Change (IPCC) and Al Gore. This started influencing some CEOs (3/10) to address climate change in their sustainability talk. Two of these companies (ABB and Atlas Copco) are already in this season establishing themselves as early adopters of sustainability frames, with focus on the environmental dimension, resonating from societal and political discourses.

Climate change
The issue of climate change dominated many media until it was overshadowed by the economic downturn. But it is not forgotten. On the contrary, the environment and improving the living conditions on our planet are an obvious priority for us. (Skanska, 2008, p. 5) However, in more specific accounts of the environmental solutions, we see that environmental discourse aligned with the discourse of economic growth, in the frame of a win-win approach (Tregidga et al., 2014). This frame is adopted by almost all CEOs (9/10).

Environmental products from resource efficiency perspective (win-win)
As one of the world's largest manufacturers of commercial vehicles, we have a responsibility to reduce the environmental impact of our production and the utilization of our products. There is no conflict between the development of products with lower environmental impact and the creation of profitable growth. (Volvo Group Annual Report, 2008, p. 5) Slightly different from Tregidga et al. (2014), our study finds that the discourse is used to project a "win-win" in the future and create hope after some financial downturns, as illustrated in the latter of the two above quotes. During and shortly after the financial crisis, companies had to cut their costs to survive on the market, prioritising new long-term oriented opportunities in form of new environmental products and services to profit from them and give a potential hope to shareholders.

Long-term perspective of growth
The Group is well positioned for long-term sustainable growth due to our position as market leader with a global presence. (. . .) Combined with the restructuring measures currently under implementation, this means that we have excellent long-term opportunities for continued growth and good profitability. (Assa Abloy, 2009, p. 6) That is how the focus on resource efficiency and new product development emerged in the CEO letters in the context of the financial crisis and the growing societal debate on the climate change problems [2]. The response to the societal debate was framed into the managerial concepts, such as resource efficiency, a "term that offers no threat to corporate attitudes and activity" (Gray, 2010, p. 49). We observed that the descriptions in the CEO letters carrying these themes at the first season were presented without any specific details.
In the quest of legitimacy, the customer is addressed as a crucial stakeholder, motivating industrial companies to develop new environmental offerings. Sustainability is thus framed as something demanded by market, not as a moral duty (Bebbington, 2007). Adapting the market products to the customers' changing demands is a convenient theme used in the letters to restore legitimacy during the challenging financial crisis, as exemplified below: For our customers, it is ultimately a matter of meeting their day-to-day needs by having vehicles with the best possible uptime. (. . .) In partnership with customers, we develop packages of products and services that deliver high efficiency, profitability, and sustainability. (Scania, 2011, p. 2) We also observe that potential improvements in the product offerings are linked to the future environmental performance of customers, but not of the industrial companies themselves. Relevant to note is that the CEOs reduce sustainability performance to the environmental dimension adapting to the socio-political discourse of climate change.

Sustainability (environmental) performance
This takes the form of significant investments in the development of products that offer improved energy efficiency in customer processes, with the corresponding reduction in the environmental footprint. Examples include solutions for the processing industry, mining industry and manufacture of wind turbines. (Sandvik, 2010, p. 4) In relation to sustainability performance, our results show that referring to the membership in leading sustainability indices, international standards, frameworks or to various national or international prizes is another way to show legitimacy of corporation: From the literature, we know that referring to awards and standards in corporate reports is an easy way for corporations to gain legitimacy (Ferguson et al., 2016). Our results reveal that the CEOs increasingly refer to the sustainability awards, indices or standards to show their symbolic power (Ferguson et al., 2016), performance and leadership in a specific market or area of expertise related to sustainability. On the other hand, companies that did not weaken financially during the crisis, either ignored sustainability talk (Securitas, 2008(Securitas, -2011 or only used some abstract decorative sentences about sustainability. An example below shows that some decorative sentences about sustainability were re-used with small variations during the whole season (2008-2011), without revealing any specific information about what exactly was done about sustainability in the business.

Memberships, indices and awards
The group is well positioned for long-term sustainable growth due to its global presence. (Assa Abloy, 2008, p. 4, 2009, p. 6, 2010, p. 7, 2011 Again, the framing in the first season reveal a typical "win-win cocktail" (Gray, 2010, p. 49) reconciling economic growth and environmental perspective (Milne et al., 2009;Beelitz and Markl-Davies, 2012) to survive and gain legitimacy (Martins et al., 2020) during and after the financial crisis. In contrast, companies like Assa Abloy and Securitas that remained financially stable after the financial crisis, did not need such a reconciliation and, thus, did not engage much in sustainability talk at this stage. Securitas, closely followed by Assa Abloy and Volvo, stands out as a company that seems to be uninfluenced by the national and transnational initiatives and only modestly influenced by the socio-political events (T4).
Furthermore, connecting to the timeline of transnational and national socio-political context, we observe the discourse of Triple Bottom Line (TBL) being a foundation of the GRI guidelines for sustainability reporting. By 2008, the GRI international guidelines promoting a TBL-approach to reporting was already used by the 77% of the 250 largest companies in the world (KPMG, 2008). Moreover, at the national level, in 2008, GRI guidelines were translated in Swedish and became mandatory for state-owned corporations to use GRI guidelines in the accounts of corporate environmental management and impact (N€ aringsdepartementet, 2007). This regulation and translation had influenced the reporting practices of other listed companies and generally increased diffusion of the GRI reporting practices in Sweden (Borglund et al., 2010). This context explains the TBL discourse, which we observe in 6 of 10 CEO letters of the large industrial companies as exemplified in quote below.

Triple bottom line
We have long recognized that non-financial issuesfrom our social, environmental and human rights obligations, to the way we treat our employeeshave a clear impact on our bottom line and on how we are perceived. (ABB, AR 2008, p. 4) We find that the transnational update of the GRI Guidelines (T4:1.2) with the intended outcome of more focus on sustainability performance is acknowledged in the CEOs' framing (T4:1.1-1.2; T5:2.8; T6:3.11, 3.15).
To sum up, by connecting the framing of the CEO letters to the dominating national and transnational socio-political discourses, our findings substantiate the idea of sustainability as a dynamic discursive concept situated in local, temporal and political spaces (Busco et al., 2018;Tregidga et al., 2018;Hallin et al., 2020). In the first season, we can summarise that environmental sustainability was a way for most of the industrial companies' CEOs to search for new opportunities after the financial crisis and create hope about the corporate future potential on the market. While only 3 of 10 CEOs (the frontrunners ABB and Altas Copco joined by Skanska) explicitly framed their talk around the topic of climate change, the framing performed by CEOs in this first season of series followed the national regulatory discourse of GRI in Sweden and the transnational societal discourse of climate change, dominated at that time. The national and transnational initiatives and regulations appear to have influenced the companies in a similar moderate extent (6/10), except for the corruptionrelated transnational initiative. Notably, the powerful socio-political events of the first season, climate change and financial crises, clearly dominated the framing of the CEO's talk in almost all companies. In the next season of film series, the framing slightly changed.

The second season (2012-2015): managing stakeholder expectations by reframing the 'win-win'
The second season of the timeline starts with the global socio-political event RIOþ20 conference, where the world leaders launched a process for development of the future Sustainable Development Goals (SDGs) and adopted guidelines for green economy policies. The RIOþ20 conference paved the way to intergovernmental partnerships aiming at sustainable development. It was then followed up by the UN Conference on Climate Change in 2015 (T2).
On the financial side, the beginning of this season was still a time of continued uncertainty and economic slowdown in the aftermath of the financial crises. However, the CEOs (6/10) continued to emphasise that the struggling years had not destroyed their companies, but instead strengthened their competitive edge, because they identified new market opportunities related to fighting climate change by increased share of environmental products in their portfolios. Thus, what they described as future opportunities creating hope for future financial growth in the first season, was now reframed towards a substantiation of expectations from both shareholders and stakeholders.
The main themes repeatedly used in the CEO letters in this season of series were market demand for corporate transformation (linked to the discourse of the socio-political events around the UN Conferences and the launch of the SDGs) and various collaborative initiatives related to sustainable development (linked to the political discourses before and after the launch of the SDGs). Our analysis revealed transformation discourse to be influential, as 7 of 10 CEOs explicitly frame their talk around the theme of transformation/transition. In the letters of the second season, the focus increased on the theme of societal transformation towards the green economy, which was a repeated topic at the UN events and conferences between 2012 and 2015. In focus of the global political agenda was re-direction of resources towards the green economy aiming at solving the problems of destroyed environments and eco-systems, ocean acidification, coastal erosion, extinction of species and human poverty. We find that this discourse influenced the way CEOs address sustainability in their letters. As illustrated below, the CEOs start talking about their readiness to contribute to transformation and reshaping of the industry to respond to societal expectations and gain legitimacy (Martins et al., 2020).

Transformation/transition
The security industry is changing and Securitas is leading this transformation, in which technology is reshaping the industry. (Securitas, 2015, p. 2) ABB is a pioneering technology leader with strong positions in attractive markets, and we remain committed to delivering attractive returns to our shareholders, based on our clear transformation agenda (ABB, 2015, p. 5) In the end of this season, the SDGs were launched, and the Paris Agreement was introduced by the UN. While there is a clear framing around transformation in the letters from this season, few CEOs (2/10) explicitly refer to the Paris Agreement but none to the SDGs.
The managerial story of business re-orientation towards more sustainable (environmental) products told in the first season, continued throughout the second season, but this time the framing allocated its focus on collaboration and partnerships related to sustainability as the way to meet stakeholders' expectations and increased market demand for environmentally friendly products and services. The political discourses before and after the launch of the SDGs and the explicit focus on the need to join forces and partner up influenced the CEOs framing. More than half of the CEOs (6/10) adopt the collaboration/ partnership frame in their talk (T5: 2.15):

Collaboration/Partnership
With our experience of working in partnership with the vehicle manufacturer, transport company and the buyer of transport services, we can take the lead in the shift towards a more sustainable transport system. (Scania, 2014, p. 8) The CEOs do not stop at bringing forward sustainability-related market demands as driving sustainability, they explicitly emphasise their confidence and ability to respond to these demands and expectations, and, more importantly, benefit (financially) from them. In essence this is not a transformation of the business, but rather about re-framing the business-as-usual into the profitable sustainability (legitimate) agenda as mirrored in the following quotes.
Our commitment and efforts meet market demand: a more sustainable product is more competitive, more cost-efficient and creates added value for customers and other shareholders. (Assa Abloy, 2012, p. 5) Furthermore, we find that framing of the "win-win cocktail" (Gray, 2010;Tregidga et al., 2014) is articulated even more explicitly, compared to the first season.
For me, this is the hallmark of sustainable transport: more efficient transport services that benefits people and society, reduce emissions and contribute to a better environment, all while achieving improved profitability. (Scania, AR 2014, p. 8) In short, we should do more with less; it is both profitable and sustainable. (ABB, AR 2015, p. 4) Related to the win-win perspective, CEOs also highlight sustainable innovation, aligned with the Swedish National CSR Policy, aiming at enhancing sustainable entrepreneurship and innovation (T5:2.2).

Sustainable innovation
In 2014, we introduced the Next Level strategy covering the 2015-2020 period to drive profitable growth and accelerate sustainable value creation in a fast-changing world. In 2015, we made significant progress toward many of our goals, reinforcing our focus on innovation, streamlining our organization and strengthening our performance culture. (ABB, 2015, p. 4) In contrast to the first season where companies (6/10) presented sustainability performance by highlighting indices, standards and awards, their framing in the second season continued (6/10) but now included more precise descriptions of targets and outcomes related to sustainability performance still with an emphasis on the environmental dimension. Some of the CEOs talk more explicitly about social and environmental impact, which is at focus of the GRI event where the new G4 guidelines were launched in 2013.

Sustainability performance
It is the first SKF manufacturing facility to receive LEED platinum certification, reducing energy and water consumption by some 50% compared to conventional factories. (SKF, 2014, p. 5) We generated CO 2 reductions of 17 percent. (Scania, 2014, p. 8) We also found that the word sustainable started turning into a prefix to financial concepts like growth and value, which creates a rhetoric of integration of sustainability and financial perspectives with each other. 4 of 10 CEOs adopt this framing (T5: 2.5). Thus, in the second season, the framing of sustainability moves from "the win-win in the future approach" (Tregidga et al., 2014) towards the integration of sustainability and business through collaboration.

Sustainable value and/or growth
As a responsible player in the security industry, we are actively adding value to our brand, reducing our exposure to the risks identified in the enterprise risk management process, and promoting sustainable growth and profit. (Securitas, 2014, p. 4) Notably, this is the first time Securitas joins other companies in adapting sustainabilityrelated frames. As shown in T5 (1.6), this company's CEO only included the long-term perspective in the letter, but did not use other frames in season 1. With some lag, they start adopting more frames, following the industry peers in season 2.
The way CEOs used the word "sustainable" as a prefix to the financial concepts can be interpreted as a framing, in which the theme of collaboration has been adapted to the new idea of integration of sustainability and business, launched by IIRC, 2013(La Torre et al., 2020. The idea of integration of financial and non-financial information started emerging in 2000s in theory and practice. The core idea is the integration of sustainability in the value creation process in corporations, building on the assumption that sustainable business and governance will increase corporate value on the capital market (IIRC, 2013). The launch of the voluntary IR framework has influenced reporting practice of listed companies and generally increased integration of financial and sustainability reporting in Sweden (Garc ıa-S anchez et al., 2013). From 2013, we also find that this discourse of integration is mirrored in the CEO letters by half of the CEOs (T5:2.3) as illustrated below.

Integration
We take the lead by integrating sustainability as a natural part of our product and business development . . . (Volvo, 2015, p. 3) Throughout the second season, some CEOs (4/10, T5:2.21) highlight their compliance with the UN Global Compact as evidence of a systematic work with sustainability issues. Below are examples illustrating how CEOs use this discourse in their letters, a decade after it emerged in 2000.

UN Global Compact
During the year, Scania embraced the United nations Global compact, an initiative for companies committed to sustainability and responsible business practices, based on ten principles concerning human rights, labour standards, environment, and corruption. (Scania, 2012, p. 7) Some years later, 4 of 10 CEOs started linking their signatory in the UN Global Compact to the corporate Codes: Code of conduct (business code) The UN Global Compact is a guiding light for us, and this is reflected in our Business Code of Practice. (Atlas Copco, 2015, p. 4) We explain this link by the national regulatory update of the Swedish Corporate Governance Code in 2015, resulting in an increase of references to the corporate Codes, like Code of Conduct or Business Code of Practice during the second season (T5:2.1). Through the lens of adaptive framing, referring to earlier global frameworks, like the UN Global Compact, can be interpreted as CEOs' way to adapt to the local regulatory initiatives in the absence of the clear regulatory guidance. In 2014, the transnational regulatory initiative EU NFRD (2014/95/EU) came into force (T2). NFRD has, however, been criticised for the absence of specific guidance or standards (Johansen, 2016). Our analysis reveals that the EU Directive influenced the CEOs framing. Half of the CEOs frame their talk around policies and risks related to sustainability, which is an intended outcome with this regulation (T5:2.9).

Policies and risks related to sustainability
Our business principles serve as the foundation for our sustainability initiatives and our goal is for all necessary risk reduction measures to be integrated into our daily work. (Alfa Laval, 2014, p. 9) In line with the intention of the NFRD, we also find that 6 of 10 CEOs now explicitly widen their stakeholder focus beyond a shareholder focus (T5:2.10).

Stakeholders in addition to shareholders
Let me extend a big thank you to our shareholders, customers, employees and other stakeholders who are contributing to Atlas Copco's sustainable productivity. (Atlas Copco, 2015, p. 5) Related to the same Directive and also to the national regulatory initiative "Corporate reporting on sustainability and diversity policy", we observe increased attention to diversity issues in the business context resulted in the diversity discourse influencing the framing of the CEO letters (T5:2.11). The framing of diversity before 2014 was limited to the gender and nationality focus but, after the EU regulation was in place in 2014, the framing also included education and wider society factors.

Diversity, before 2014
Today, Sandvik has a management team that better reflects the Group's diversity profile, with a more international character and a better gender balance than before. Sandvik will be a company where everybody has the same pre-requisites, regardless of gender or nationality. (Sandvik, 2013, p. 3)

Diversity, from 2014
Diversity is another key to success, whether it is gender, age, nationalities or education. (Atlas Copco, 2015, p. 4) To summarise, our analysis shows that, in the second season, the CEOs adapted their sustainability talk to the socio-political discourses, by re-framing the "win-win" and dressing it in the discourse of transformation collaboration, integration and diversity. These re-framing is influenced by the increasing expectations from stakeholders in addition to shareholders, which is ostensibly an indication of the changing legitimacy concerns (Martins et al., 2020). Thus, we argue that the frame of "win-win" is not static but is dynamically changing over time by adapting to the national and transnational initiatives and socio-political events.

4.3
The third season (2016-2019): emergence of multifaceted sustainability and slow arrival of urgency During the third season of the studied timeline, the climate change debate started shifting towards the rhetoric of climate crisis and urgency. Moreover, this period of time was rich of scientific and social debates about critical environmental and social issues, induced by investigative initiatives, such as Panama papers and IPCC and IPBES reports. Influence came also from social activism, such as the global "Fridays for Future" strikes initiated by the Swedish activist Greta Thunberg and the Paris manifesto, initiated by French business school students (T6:3.18-3.22). At the same time, the third season harvested quite a number of new policies and regulatory initiatives, both national and transnational. In this context, the thematic categories in the CEO letters also started changing. We find that that the framing of environmental sustainability shifts towards framing hope to the future generations by continuously articulating the discourse of transformation/ transition of the industries (6/10, T6:3.13), but this time addressing it explicitly to the future generations, as illustrated below.

Transformation/transition
The world is moving ever closer to that inevitable point in time when sustainable transport solutions become the only viable option and a "new normal." In 2017 Scania intensified its efforts to drive the shift towards a sustainable transport system. (Scania, 2017, p. 6) ASSA ABLOY is committed to reducing its environmental footprint and to help to mitigate climate change, to meet the needs of future generations. (Assa Abloy, 2019, p. 5) Here, it is important to add that the discourse of sustainable innovation that emerged in season 2, continues and increases in season 3 (T6:2.2).
Furthermore, compared to the first season, when CEOs talked about future to address the expectations of shareholders, the observations of the third season clearly show that they talk about the future in a different way. Now they address the needs and expectations of future generations and give them hope. This is a significant move in the CEOs' film series, connecting back to the original Brundtland definition of sustainable development, meeting "the needs of the present without compromising the ability of future generations to meet their own needs" (UNWCED, 1987, p. 8). CEOs (7/10) continue to increase their focus on a broader stakeholder group (T6:3.2) and now they explicitly name various groups of their audience in their letters (2016)(2017)(2018)(2019). Some CEO letters define the audience already in the titles of the letters, "dear Shareholders, Customers, Partners and Employees" (ABB AR 2016;. This is in contrast to "Dear shareholders" in the titles before 2016. This multi-stakeholder approach, earlier promoted by GRI, is also underlying the rhetoric of the NFR Directive (2014/95/EU) and, specifically, its implementation in Sweden [3] (T6). To maintain legitimacy in a context of national implementation of the NFR Directive that requires environmental, social and employee-related disclosures, the CEO started addressing the stakeholders right in the top titles of the letters. Thus, the national implementation of the transnational regulation has slightly changed the way CEOs are framing the stakeholders, now articulating them as their key audience (T6:3.2). Furthermore, the CEO letters adapt their language to the ongoing socio-political discourse of urgency (Tregidga and Laine, 2022), resonating with the arguments of scientists and environmental activists. Thus, the CEOs adapt frames accentuating the need for climate action (4/10, T6: 3.22, 3.24), starting acknowledging (2/10) climate crises/climate urgency (T6:3.21, 3.23).

Climate action and Climate crises/Climate Urgency
One of the world's biggest challenges is to decouple economic growth from its environmental impact. To achieve the Paris Agreement target of limiting the rise in global temperatures to fewer than 2 8C, the world will need to turn even faster to renewables and e-mobility, as well as dramatically improve energy efficiency. (ABB, 2017, p. 8) In addition, the science discourse started emerging in 2019 in one of the CEO letters (T6:3.25). It is Scania, a producer of heavy vehicles and transport solutions that is a frontrunner of the discourse around themes of climate crisis, urgency and science since 2018 when discourses from multiple new regulatory initiatives emerged (T6:3.12-3.25). While the link between citizen science and sustainability reporting has recently been articulated (Millar and Searcy, 2020), we recognise that science started influencing CEO's framing of sustainability. Our analysis indicates a trend when very few early adapters start adapting a science discourse, which, in the next season, is also adapted by more CEOs (T6:1.3; T5:2.12). Therefore, we suggest to follow how the science discourse develops in the coming years, influenced by, for example, a work of IPCC and IPBES.

Science
Our planet and its climate will not wait. Science dictates that we as a society must half CO2 emissions every decade to meet the global target as defined in the Paris agreement. (Scania, 2019, p. 6) The concept of circular economy articulated by the European Commission in 2015 was also included in the framing of the third season's CEO letters (4/10, T6:3.20) to respond to the urgency discourse.

Circular economy/models
We know we can reduce the waste in the value chain and we are totally committed to drive the circular use of resources to its full potential. (SKF, 2019, p. 8) The discourse of urgency around social and environmental challenges was underlying earlier transnational frameworks and agreements, such as Paris agreement and UN SDG framework. The corporate leaders relate to these globally accepted international frameworks and regulations, because they are under regulative pressure triggered by the urgent societal debate, which has spotlighted the unsustainability of the business-as-usual. In this context, the leaders realise that corporate legitimacy can be threatened if they do not respond to it (Suchman, 1995). Here, the frameworks and regulations become a way for them to relate to existing legitimate frames, as illustrated below. The last excerpt illustrates that CEOs' rhetoric of vital importance of sustainability issues was urged by the regulations and voluntary corporate commitments. The references to frameworks and international agreements, such as the Paris Agreement (from 2 to 4 of 10, T5:2.12) and the SDGs (from 0 to 7 of 10, T5:2.14) in the letters also increased in this season compared to the second where these were launched. Thus, we can argue that the regulative landscape including regulatory frameworks and international agreements become a way for CEO to rhetorically manage legitimacy by more explicitly referring to them in their sustainability talk: The Paris Agreement on Climate Change and the UN's 17 Sustainable Development Goals (SDGs), have reinforced the sense of urgency when it comes to continuing to incorporate sustainability further into our business plan. (Scania, 2016, p. 6) For 2019, we see sustainability, particularly relating to climate impacts, becoming even more important because of both regulations and voluntary corporate commitments . . . (Skanska 2018, p. 3) A possible explanation of this development is a significantly increased number of both national and transnational regulatory initiatives in the end of the second and during the third season, which created a strong external pressure on the industrial companies. In addition, we find that the discourse of sustainable development as it is framed by United Nations is significantly more visible in the letters of the third season. Especially, we find SDG 17 influencing the discourse of collaboration (T5:2.15), which was sound in the second season (6/10), and remained in the third season (6/10).
Another focal topic increased in the letters of this period was employment. It included the descriptions of working conditions and training considering the ongoing technological shift towards digitalisation in the industrial sector. We connect this thematic focus to the two events of social activism "Fridays for Future" and "Paris manifesto", both driven by young generation (potential future employees) and both highlighting the urgency of climate change and transformation/transition to carbon neutral economy. We find that discourses of these events significantly influenced the CEOs talk. While 5 of 10 CEOs framed themselves as climate-friendly employer (T6: 3.18), almost all of the CEOs (9/10, T6:3.19) include an employee focus and specifically a frame related to attracting employees.

Attracting employees/focus on employees
Going forward, we will continue to provide our employees with attractive opportunities for personal and professional development, and to encourage inclusion, diversity and well-being in the workplace, as we foster an environment in which people have the confidence and are encouraged to take risks and aim at delivering results for a sustainable high performance. (ABB, 2019, p. 10) To continue, the talk about corruption including anti-corruption policies, which was only modestly articulated in season 1 (2/10, T4:1.3), with some lag increased in season 2 (7/10, T4:1.3), and became an even more common frame in the CEO letters (8/10, T6:3.17). In addition, diversity (T5:2.11) is a continued discourse (5/10) in the letters and sustainability performance even increases (7/10, T6:3.11,3.15) in the third season. A difference from earlier seasons is that the CEOs often combine these dimensions, to continue framing the multi-dimensional integrated "win-win" approach to sustainability promoting sustainable value and growth. One of these dimensions, sustainability performance, is framed differently compared to the previous seasons, as it now has a special emphasis on environmental performance targets. We interpret this multi-dimensionality as an effect of a number of national and transnational policy and regulatory initiatives emerging in addition to already existing initiatives from season 2. Such new initiatives at the transnational level were establishing EU HLEG on sustainable finance, EU TEG, the European Green Deal and another EU Directive (EU, 2019/2089) on sustainability disclosure benchmarks (T6:3.14). They were accompanied by the related national policy and regulatory initiatives, such as transposition of the NFRD, as well as introduction of a Sustainable Business Guide (2016) and ESG reporting guide (2017) in Sweden.
Below is an example, in which the CEOs mention various dimensions of sustainability as vital elements of their business model. However, the words are empty, they do not specify any essential problems of planetary condition, biodiversity distraction and human suffering because of the "business-as-usual" in many industries. Ostensibly, the corporate discourse, captured by the managerial perspective, is not reflecting the substance of sustainability of planet and people, but only briefly mentioning dimensions of sustainability as a kaleidoscope of various colours (Milne and Gray, 2007).

Sustainability framing in CEO letters
Working for human rights, improved labor conditions, a better environment and against corruption is not only the ethically correct thing to do but also a natural part of our business model. (Atlas Copco, 2016, p. 4) Even though sustainability is framed as a kaleidoscope of different dimensions in the third season, it is only the issues of carbon emissions and diversity that are specified in the letters. The other dimensions are just mentioned in general claims, without specific descriptions of their implementation into operations. The excerpts below exemplify how the environmental dimension of sustainability is detailed in the CEO letters (8/10, T6:3.13).

Reduced carbon emissions
It remains the most impactful way we can reduce carbon emissions and contribute to our customers' and our own sustainability ambitions. One prominent example is the VSD þ technology used in compressors, generators and vacuum pumps, which offers our customers notable energy savings. Another example is Atlas Copco abatement systems that remove greenhouse gases in the semiconductor industry. (Atlas Copco, 2019, p. 3) Next, we illustrate the thematic category of diversity:

Diversity
With employees in about 90 countries, we know that diversity is an asset, regardless of nationality, gender, age or education. For example, our 459 most senior managers represent 53 nationalities. In 2017, the share of female employees was 18% while 22% of total external hires and 31% of recent graduates hired were female. (Atlas Copco, 2017, p. 5) That CEOs write more concretely and add examples concerning environmental and diversity issues is not coincidence. We explain it by the early national regulation and public debate of these two issues in Sweden -The Environmental code (Milj€ obalken) from 1998 [4], requiring environment-sensitive companies to report on their environmental impact and the legislation related to diversity in corporate management by requiring Swedish companies to report on gender distribution [5]. The earlier regulated topics are thus given more specific attention in the letters, compared to the other sustainability topics, only briefly mentioned in the letters. Therefore, the early national tradition to regulate certain issues enhances the influence of the recently introduced regulation, like the NFRD. In this context, our results highlight the importance of substantiating the critical planetary and societal issues in the regulations, to influence CEOs' articulation of these aspects of sustainability. Even if being captured by the managerial discourse (Gray, 2010), the influence of the external discourses emerging from the civil society, policymakers and regulators change the CEOs' framing of sustainability over time. We argue that understanding this influence is essential for policymakers, regulators and civil society activists in their process of developing future strategies and enabling changes in how companies frame sustainability (and, hopefully, transform their businesses in the future). In letters of the third season, 7 of 10 CEOs view sustainability through the scope of sustainable business and efforts (T6:3.5). We find that key performance indicators, focus areas and the future-oriented goals and targets are used as managerial tools in response to the national and transnational regulatory initiatives, reporting on how they design sustainable business and efforts related to sustainable development.

Sustainable business/efforts
Our sustainability focus areas encompass Health and Safety, Ethics, Green, Community Investment and Diversity and Inclusion. These are closely linked to the United Nations' (UN) Sustainable Development Goals, and they help us continuously uphold the universal sustainability principles defined by the UN Global Compact. (Skanska, 2018, p. 3) Finally, it is important to mention that some regulatory initiatives only were mentioned but did not influence explicitly the framing of sustainability in the CEO letters, for example TCFD (T6:3.8). Also, we did not see any influence of the ESG implementation guide (national initiative) (T6:3.6).
To conclude, our takeaway from the analysis of the third season is that the influence of most of the socio-political and regulatory discourses on the CEOs' framing of sustainability increases over time. We can also claim that the CEOs' framing is changing slowly. An intensified number of national and transnational policies and regulations and other sociopolitical events in recent years has not yet changed framing of sustainability in all the studied industrial companies. It means that the current regulations leave a large room for framing sustainability with empty words, which still allows companies to look legitimate, even if the urgent problems related to the planetary and social crises are ignored in many CEO letters. Our results suggest that regulators and civil society have power to change the way sustainability is framed by the CEOs of industrial companies, especially, when regulators and civil society join forces and increase pressure by consolidating their requirements and expectations from industrial companies at all levels.

Concluding remarks
Prior research suggests that societal expectations of corporate change towards sustainable businesses motivate CEOs to take the opportunity and promote the ideology of sustainable business reconciling shareholders' and stakeholders' interests (Milne et al., 2009;Beelitz and Markl-Davies, 2012). CEOs are seen as influential leaders of this ideology  and the CEO letter is one of the means for conveying influential ideas (M€ akel€ a and Laine, 2011), such as a "win-win" relation between sustainable development and economic profits (Gray, 2010;Tregidga et al., 2014). To add to this perspective, this study provides insights into the external powers that can influence business leaders' communication about sustainability.
By addressing the research question how sustainability is being framed and adapted to national and transnational sustainability discourses over time? This study contributes to prior research by illustrating the potential for policymakers, regulators and civil society to influence the CEO sustainability talk. While existing studies on CEO letters and, more generally, corporate sustainability accounts emphasise the profit-driven "win-win" approach to sustainability in corporate rhetoric (Gray, 2010;Tregidga et al., 2014), our results illustrate that the meaning of "win-win" adapts in the process of alignment with continuously changing socio-political discourses related to sustainability. For example, in the time of weakened corporate financial performance (season 1), CEOs promoted a "winwin" to sustainability by emphasising environmental discourse as part of the future economic growth narrative.
It was, however, reframed in Season 2, where the CEOs broadened their focus beyond environmental sustainability. Now new themes were emphasised (transformation, collaboration, integration and diversity) to nuance the conditions for achieving the "winwin" in the future. Here, expectations beyond the shareholders were also included in the narrative. Over time, the number of national and transnational policies, regulations and sociopolitical events increased and accumulated (from 5 in Season 1 to 13 in Season 3; Tables 4-6), which we link to the increased number of thematic categories in the letters (from 6 in Season 1 to 36 in Season 3). In the third season, the meaning of the "win-win" was again modified, this time by emphasising future generations and framing "win-win" as an alignment between corporate sustainability performance and companies' long-term survival. Worth mentioning, while social dimensions are included in the framing, it is modest compared to the environmental frame. We believe that the CEOs might find it is more difficult to frame the "win-win" in relation to social dimensions of sustainability where the relationship to financial performance is more difficult to establish and articulate.
Thus, we argue that the CEO talk of sustainability is an exercise of adaption to the socio-political discourses in a specific temporal and spatial context. Here the two theoretical concepts togetherlegitimacy and framingbuild the theoretical notion of adaptive framing. Previous research shows that companies adapt the rhetoric of environmental disclosures in response to changing social and institutional context (Arvidsson, 2023;Laine, 2009). Our results enrich this understanding by structuring a contextual timeline of national and transnational policies, regulations and other sociopolitical events and discussing its influence on the themes included in each CEO letter being an episode of a film series (Goffman, 1974(Goffman, , 1981Czarniawska, 2006) addressing sustainability in a company. By making these linkages over time and thus illustrating adaptive framing of sustainability in CEO letters, this study adds to previous studies illustrating that the meaning of sustainability is dynamically changing over time (Busco et al., 2018;Tregidga et al., 2018;Hallin et al., 2020). With the increase of national and transnational policies and regulations related to sustainability, the CEOs simultaneously communicated different frames of sustainability as a kaleidoscope of various meanings of sustainability. However, the adaptation is slow over time. Yet, we clearly observe that the accumulation of policies, regulations and other socio-political events have an effect on the increasing number of sustainability frames, especially in season 3 (36 thematic categories; T6). The adaptive framing in CEO letters becomes more pronounced in the third season when discourse of urgency, emerging from the socio-political events and new regulations related to sustainability, intensifies (Tregidga and Laine, 2022). Ostensibly, there is a mutual relation where business leaders influence the society (M€ akel€ a and Laine, 2011;Craig and Amernic, 2004) and the society influence the business leaders. To conclude, this study emphasises the potential power of policymakers, regulators and civil society to influence CEOs' framing of sustainability, thus, contributing to the existing research of CEO rhetoric (M€ akel€ a and Laine, 2011;Craig and Amernic, 2004).
Theoretically, in the existing accounting research, the notion of framing has mainly been used in a static meaning of managing impressions, as an image frame (Beelitz and Markl-Davies, 2012;Perkiss et al., 2020), inspired by the earlier work of Goffman (1959). To contribute to these studies, our research uses Goffman (1974)s' notion of dynamic framing and Suchman (1995)s' notion of legitimacy, which is also a dynamic (time and place specific) process of communication and alignment between the organisation and its stakeholders. These two notions allowed us to theoretically discuss the adaptive framing, in which framing patterns gradually changed over time under the influence of transnational and national sociopolitical context. If CEOs adapt their rhetoric for legitimacy purposes, they are also managing the risks of losing legitimacy over time (Martins et al., 2020). Here, adaptive framing is a way for CEOs to manage these risks and align with their stakeholders' expectations. More research looking into the links between CEO framing of sustainability and corporate risk assessment can therefore be a relevant avenue for future research.
This study has implications for further research into the longitudinal influences of the socio-political discourses on business leaders' rhetoric. We call for more studies exploring the power (or absence of power) of various stakeholders to influence business leaders' framings and conceptualisations of sustainability. In the context of sustainable development, a nuanced understanding of various stakeholders' potential to influence companies is much needed for the future policy-and practice development (Bebbington and Unerman, 2020). Considering that our results illustrate the potential of national and transnational policies, regulations and socio-political events to influence business leaders' framing of sustainability in the CEO letters, this has implications for how these policies and regulations can be revised and further developed. We find that in the third season (2016-2019) of the studied timeline, some CEOs started addressing the urgency of climate crisis, using the concept of circularity in their talk about sustainable products and services and explicitly acknowledging the importance of regulations. The existing policies and regulations, however, leave a large room for framing sustainability with empty words. An exception here is the long national tradition to regulate certain aspects (for example regulations related to the Environmental Code and diversity reporting in Sweden), which lead to more substance in the CEO sustainability talk related to these aspects later in time. We argue that an understanding of the roles of socio-political discourses in influencing CEO framing of sustainability can have implications for how policymakers, regulators and civil society could join forces and together harmonise conceptual tools and language of social and environmental sustainability. We believe that this could be a path of guiding business leaders' rhetoric more effectively towards Agenda 2030. From an organisational perspective it is also important for them to acknowledge the interrelation between different socio-political discourses and adaptive framing of sustainability. An opportunity for organisations can be adopting a proactive approach aimed for a mutual influence (between organisations and policymakers) and introduce new sustainability perspectives and frames that have yet not been articulated by policymakers.
Finally, the methodology and scope of this study do not allow to provide detailed explanations as to why some of the studied industrial companies adapted certain frames early and others were lagging behind and only joined the frontrunners in later seasons. We leave these relevant questions to be approached in future case studies analysing corporate rationales behind adapting different sustainability-related frames. Here, we encourage future research to connect companies' adaptive framing to, for example, proactive vs reactive reporting strategies driven by specific rationales (Buhr et al., 2014). Notes 1. We use Brundtland Commission's definition of sustainable development (UNWCED, 1987, p. 8) 2. The Nobel Peace Prize for 2007 was awarded to the IPCC and Al Gore for their efforts to obtain and disseminate information about the climate challenge. Documentary An Inconvenient Truth (2006) was one of the means to communicate climate change problem to the society. Source: https://www. nobelprize.org/prizes/peace/2007/gore/facts/ 3. Swedish government mandated this legislation for not only public large entities of 500 employees (as the EU). The reporting obligation applies to all types of Swedish companies that fulfil at least two of the three criteria: number of employees over250; net turnover over SEK350 million; balance total over SEK175 million.