Summary
Updated Aug 31, 2026
William Spencer Marshall is Co-Founder and CEO of Planet Labs PBC (PL). 15 SEC Form 4 filings on record going back to 2024, most recently on 14 July 2026. Most recent open-market trade: sold $5.18M of PL on 14 July 2026. Lifetime open-market sales: $19.17M.
Recent Transactions
20Every recent SEC Form 4 transaction William Spencer Marshall has reported, most recent first.
Trading Pattern
InsiderAlpha's records for William Spencer Marshall go back to 2024: 15 primary Form 4 filings, an average of 5.0 per year. 4 recorded transactions carry a Rule 10b5-1 flag, meaning they were pre-scheduled under a written trading plan rather than discretionary.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies William Spencer Marshall files at. Multiple unrelated insiders buying the same stock within a short window, cluster buying, has historically been one of the strongest Form 4 signals.
- Ashley F. Johnson - $13.52M of PL open-market activity in the last 12 months
- Robert H. Schingler - $7.60M of PL open-market activity in the last 12 months
- Carl Bass - $5.90M of PL open-market activity in the last 12 months
- Kristen Robinson - $2.22M of PL open-market activity in the last 12 months
- Ita M. Brennan - $1.62M of PL open-market activity in the last 12 months
- Vijaya Gadde - $535K of PL open-market activity in the last 12 months
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
Frequently Asked Questions
Who is William Spencer Marshall?
William Spencer Marshall is a corporate insider, tracked as Co-Founder and CEO of Planet Labs PBC (PL). InsiderAlpha holds 15 primary Form 4 filings for them, the earliest from 2024, updated as new SEC EDGAR filings are processed.
How many SEC Form 4 filings has William Spencer Marshall submitted recently?
2 primary Form 4 filings in the last 90 days, covering 1 company.
Has William Spencer Marshall been buying or selling stock?
Recorded transactions: 0 open-market purchases and 4 open-market sales ($19.17M) across all tracked filings.
Where can I see all of William Spencer Marshall's SEC filings?
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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