Summary
Updated Aug 31, 2026
MAINSAIL GP III, LLC is 10% Owner of Brilliant Earth Group, Inc. (BRLT). 2 SEC Form 4 filings on record, most recently on 26 August 2026. Most recent open-market trade: sold $64K of BRLT on 12 August 2026. Lifetime open-market sales: $64K.
Recent Transactions
4Every recent SEC Form 4 transaction MAINSAIL GP III, LLC has reported, most recent first.
Trading Pattern
InsiderAlpha's records for MAINSAIL GP III, LLC go back to 2026: 2 primary Form 4 filings, an average of 2.0 per year. No transaction on record carries a Rule 10b5-1 flag - the filings look discretionary rather than pre-scheduled, which makes their timing more informative as a signal.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies MAINSAIL GP III, LLC 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.
- Sharon Dziesietnik - $70K of BRLT open-market activity in the last 12 months
- Gavin Turner - $64K of BRLT open-market activity in the last 12 months
- Jennifer Noel Harris - $40K of BRLT open-market activity in the last 12 months
- Jeffrey Chuenhong Kuo - $14K of BRLT open-market activity in the last 12 months
- Eric Scott Grossberg - $13K of BRLT open-market activity in the last 12 months
- Beth Tamara Gerstein - $13K of BRLT 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
What is MAINSAIL GP III, LLC?
MAINSAIL GP III, LLC is a corporate entity, tracked as 10% Owner of Brilliant Earth Group, Inc. (BRLT). InsiderAlpha holds 2 primary Form 4 filings for it, the earliest from 2026, updated as new SEC EDGAR filings are processed.
How many SEC Form 4 filings has MAINSAIL GP III, LLC submitted recently?
2 primary Form 4 filings in the last 90 days, covering 1 company.
Has MAINSAIL GP III, LLC been buying or selling stock?
Recorded transactions: 0 open-market purchases and 1 open-market sale ($64K) across all tracked filings.
Where can I see all of MAINSAIL GP III, LLC'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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