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Total declarations
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▲ Purchases (0 ops.)
▼ Sales (0 ops.)
Explore the full record of transactions filed by SEIFERT THOMAS J, Chief Financial Officer. Director active across 2 companies, notably Cloudflare, Inc.. Aggregated, 67 filings have been recorded. The latest transaction was disclosed on 15 April 2026 — Retenue fiscale. Regulator: SEC (Form 4). The full history is openly available.
Declarations67 total
US$445,3712,944 shares@ US$151.28080.0006% mcap45.1% of flow
Class A Common Stock
SEC:0001473289-26-000012·
€445,3712,944 shares@ €151.28080.0006% mcap22.5% of flow
Class A Common Stock
SEC:0001473289-26-000012:0·
US$542,6652,943 shares@ US$184.39170.0008% mcap54.9% of flow
Class A Common Stock
SEC:0001473289-26-000010·
€542,6652,943 shares@ €184.39170.0008% mcap27.5% of flow
Class A Common Stock
SEC:0001473289-26-000010:0·
10,000 shares
Class A Common Stock
SEC:0001473289-26-000006·
10,000 shares
Class A Common Stock
SEC:0001473289-26-000006:0·
10,000 shares
Class A Common Stock
SEC:0001473289-26-000002·
10,000 shares
Class A Common Stock
SEC:0001473289-26-000002:0·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000017·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000017:0·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000013·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000013:0·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000011·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000011:0·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000009·
10,000 shares
Class A Common Stock
SEC:0001473289-25-000009:0·
02,631 shares0
Common Stock
SEC:0001111928-22-000089:0·
10,000 shares
Class A Common Stock
SEC:0001209191-22-024446:0·
10,000 shares
Class A Common Stock
SEC:0001209191-22-021626:0·
10,000 shares
Class A Common Stock
SEC:0001209191-22-019852:0·
10,000 shares
Class A Common Stock
SEC:0001209191-22-011676:0·
036,277 shares0
Class A Common Stock
SEC:0001209191-22-007269·
036,277 shares0
Class A Common Stock
SEC:0001209191-22-007269:0·
20,000 shares
Class A Common Stock
SEC:0001209191-22-004040·
20,000 shares
Class A Common Stock
SEC:0001209191-22-004040:0·
25 of 67 declarations
About SEIFERT THOMAS J
Thomas J. Seifert is an experienced finance executive and public-company director with a career spanning technology, cybersecurity, wireless distribution, and industrial innovation. His most notable current role is Chief Financial Officer of Cloudflare, a position he has held since June 2017. At Cloudflare, he oversees the company’s global finance organization and helps prepare the business for continued scale in the internet performance and security market. When he joined, Cloudflare described him as a finance leader with deep knowledge of U.S. and European markets and a strong understanding of the demands facing a fast-growing public company. Before Cloudflare, Seifert served as Executive Vice President and Chief Financial Officer at Symantec from March 2014 to 2017. During that period, he helped lead the company’s financial and strategic transformation and oversaw the acquisition of Blue Coat. Prior to Symantec, he was Executive Vice President and Chief Financial Officer at Brightstar, where he was responsible for financial operations, corporate accounting, treasury, and information technology. These roles established him as a senior finance leader with broad operating experience and a track record in managing complex corporate change. Seifert also has meaningful board experience. He joined the Board of Directors of IPG Photonics in 2014, adding public-company governance experience in an industrial technology business known for fiber laser systems. His board service strengthened his profile in audit oversight, strategic supervision, and long-term value creation. He also served on the board of CompuGroup Medical SE from 2018 to 2020. Across his career, Seifert has been associated with disciplined financial leadership, investor credibility, and support for companies navigating growth, operational complexity, and strategic transitions.
