Outside-Director Form 4: Why Tim Cook's Nike Trades Show Up

SEC Form 4 reporting is per-insider, not per-company. When Tim Cook bought 25,000 shares of Nike at $42.43 in April 2026, the transaction appeared on his Form 4 filing — alongside his Apple cashless-exercise activity from earlier that month. Most retail-investor news flow does not surface the Nike trade because the filing is indexed under Cook's CIK (0001214156), and Apple-focused screens skip the cross-company line items. The Nike trade is one of the cleanest discretionary-purchase signals (code P) in any recent Form 4 filing, and it is exactly the kind of cross-company insider signal that gets missed when readers search by company instead of by insider.

This guide explains how cross-company Form 4 reporting works, why outside-director purchases are often the highest-information signals available, and how to systematically find these filings without relying on company-specific news flow.

How cross-company Form 4 reporting works

Form 4 ("Statement of Changes in Beneficial Ownership") is filed by individuals who hold Section 16 reporting positions — officers, directors, and 10%-or-greater beneficial owners — at any US-listed public company. The filing requirement attaches to the insider, not to a specific company. When an insider has Section 16 obligations at multiple companies (such as a CEO who also sits on an outside board), every reportable transaction across any of those companies appears in the insider's Form 4 filings.

The mechanics:

1. Each Form 4 specifies the issuer (company) being traded in. The 'Issuer Name' field on the cover identifies which company's shares were affected.
2. The insider's reporting CIK is constant across filings; the issuer CIK varies depending on which company the transaction involves.
3. A single Form 4 can cover transactions in multiple issuers if filed on the same date — the issuer is identified at the transaction-line level.
4. The SEC EDGAR full-text search indexes by insider CIK. The per-company filings page indexes by issuer CIK. Both surface the same data; the index is different.

For Tim Cook specifically, this means:

• His Apple-related transactions (option exercises, share sales, RSU vests) appear on Form 4s with issuer = Apple Inc. (CIK 0000320193).
• His Nike-related transactions (open-market purchases) appear on Form 4s with issuer = Nike Inc. (CIK 0000320187).
• Both sets are indexed under Cook's reporting CIK (0001214156). The SEC EDGAR insider history page for Cook shows everything; the per-company page for Apple shows only the AAPL transactions.

Why outside-director purchases are high-information

When a CEO of one company buys stock as an outside director of another company, three properties make the signal unusually clean:

1. The purchase is discretionary (code P). Outside-director purchases are almost never plan-driven or compensation-mechanical. The director is using personal capital to acquire shares at the prevailing market price. There is no tax-cover obligation, RSU-vest mechanic, or scheduled-plan execution forcing the trade.
2. The director has board-level information access. Outside directors see quarterly board materials, internal financial projections, strategic-plan slides, and competitive-landscape briefings that no public market participant sees. Their information set is meaningfully different from public investors'.
3. The transaction is small relative to total compensation. Outside directors typically receive cash retainers, RSU grants, and per-meeting fees that exceed any open-market purchase they might make. The decision to spend personal capital on additional shares — when the cash-and-RSU compensation already provides exposure — reflects high conviction beyond compensation mechanics.

Tim Cook's Nike purchases capture all three properties. Cook is on Nike's board, so he is buying with board-level information. The transactions used code P, indicating discretionary open-market purchases with personal capital. And the $4 million combined investment across two purchases is small relative to Cook's $50+ million annual Apple compensation — he chose to commit personal cash to Nike specifically.

How to find outside-director cross-company filings

Four systematic approaches:

1. Insider-CIK indexed search. Pull the SEC EDGAR insider history page for any major CEO or known board member (Cook, Iger, Dimon, Buffett, Munger's historical filings, etc.). The page lists every Form 4 filing for that insider across all issuers. Filter for issuers other than their primary company.
2. Form 4 code-P scans. Discretionary purchase signals (code P) are inherently scarcer than sales. A code-P scan across major CEO insider filings often surfaces 1-3 high-information cross-company purchases per quarter.
3. Director cross-reference. For any major US public company, the proxy statement (DEF 14A) lists outside directors. Cross-reference each director against SEC EDGAR insider search to see their filings across all boards. Outside directors who serve on 3+ boards generate the most cross-company signals.
4. Form 4 footnotes. Many cross-company transactions include footnotes explaining the dual capacity ('reporter is also a director of X'). These footnotes are searchable in the SEC EDGAR full-text engine.

Common cross-company insider patterns

Three patterns recur in our database:

• CEOs of mega-caps serving on consumer-brand boards. Tim Cook on Nike's board. Bob Iger formerly on multiple boards. Mary Barra at GM has held outside board positions. These cross-company CEOs typically use board-level information sets to identify value or growth opportunities not visible to the public market.
• Founders serving on industry-adjacent boards. A medical-device founder might sit on a separate biotech board; a software founder might sit on a payments-network board. Their cross-company purchases often reflect industry-conviction signals that span beyond their primary company's franchise.
• Activist investors taking board seats. When Carl Icahn or similar activists land board seats at target companies, their open-market purchases of the target's shares appear on Form 4 filings — and the signal is unusually clean because the activist is documenting their own thesis publicly.

What to do with these signals

Three rules for retail readers:

1. Don't reflexively follow every outside-director purchase. Some are small commitments to board-required share ownership minimums (most US public-company directors are required to hold a minimum number of shares within X years of joining the board). Read the size of the purchase against the insider's known compensation to gauge whether it's structural ownership-minimum compliance or genuine conviction.
2. Watch for averaging-down behavior. Multiple purchases by the same outside director as the stock falls — Cook's December 2025 ($58.97) and April 2026 ($42.43) Nike purchases — strongly indicate directional conviction rather than ownership-minimum compliance.
3. Cross-check with institutional flow. If outside-director purchases align with active institutional managers building positions (visible in 13F filings), the signal is reinforced. If they conflict with institutional sales, the cross-company director might be early or wrong.

Examples from recent filings

• Tim Cook: Apple CEO, Nike outside director. 50,000 NKE shares at $58.97 (Dec 22, 2025) + 25,000 NKE shares at $42.43 (Apr 10, 2026) = $4M total averaging-down on Nike.
• Bob Iger (historical): Disney CEO, formerly served on multiple outside boards.
• Mary Barra: GM CEO, has held outside-director positions where her board-level industrial insight has informed cross-company filings.

For the active feed of cross-company insider purchases, see our institutional signals feed. For related Form 4 reading techniques, see the related P-code purchase signals and multi-class Form 4 Table I/II guides in the explainer hub.