We conducted descriptive statistics of shareholder ownership in the seafood industry based on the publicly listed companies with seafood involvement identified by McCarron (19) (table S5 and data file S1). Shareholder information was retrieved from the FactSet Ownership Download Builder on 23 October 2017 (www.factset.com) using the “all shareholder” view to account for any unconsolidated or unlisted part of the company. We focused on market capitalization and the percentage of ownership, defined as the proportion of outstanding shares of the company held by any investor. The completeness of the data depended on company disclosure. We found information for 160 companies with a combined market capitalization of $520 billion, an average of 57% ownership disclosed, and 3250 unique shareholders consolidating into 2561 parent shareholders (e.g., 16 different BlackRock funds consolidating into “BlackRock Inc.”) (data file S1). More than 93% of all listed companies were engaged in processing/wholesale. Of those, 32, 25, and 10% were also involved in aquaculture, capture fisheries, or both, respectively. Only four companies were engaged only in capture, and seven were engaged only in aquaculture (data file S1).

Web searches for each shareholder name were conducted to classify unique shareholders into five broad categories: financial institutions (n = 1832; e.g., banks, insurances, pension funds, private equity firms, hedge funds, and mutual funds), individuals (n = 732; including family-owned trusts), nonfinancial corporations (n = 610; e.g., private and public companies, holding companies, and business associations), foundations/nonprofit (n = 18; e.g., foundations, endowments, and nonprofit organizations), and governments (n = 12, including sovereign wealth managers). Forty-six shareholders (mostly private companies) could not confidently be classified into one of these categories (data file S1). Analyses and network visualizations were performed using R version 3.3.2 with a focus on ownership values above 5 and 10%, representing identified thresholds of potential influence over corporate operations and governance (47). Statistical scripts and data are available on GitHub (https://github.com/JBjouffray/SeafoodFinance).