Steven B. Klinsky - SEC Form 4 Insider Trading Activity
Summary
Updated Aug 3, 2026
Steven B. Klinsky is a corporate insider tracked by InsiderAlpha. No SEC Form 4 filings recorded in the last 90 days. Lifetime open-market purchases: $27.72M. Historical track record: 2/5 stars across 64 tracked purchases.
Profile
Steven B. Klinsky holds the role of Director at New Mountain Finance Corp (NMFC). Klinsky's filing history also covers New Mountain Private Credit Fund. Klinsky has reported 20 insider filings with the SEC since 2024. The most recent filing was in March 2026.
| Role | Director, 10% Owner |
|---|---|
| Notability | 36/100 |
Board memberships
- New Mountain Finance Corp
- New Mountain Private Credit Fund
Reported roles
- Director
- 10% Owner
Awards & honors
- Founder of New Mountain Capital
- Director at New Mountain Finance Corp
Track Record
InsiderAlpha computes a forward-return-based score for every insider with enough Form 4 purchase history. The metrics below reflect realised performance after each tracked open-market purchase.
| InsiderAlpha rating | ★★☆☆☆ (2/5) |
|---|---|
| Total purchases tracked | 64 |
| Purchases with forward-return data | 63 |
| 30-day win rate | 30% |
| 90-day win rate | 59% |
| Avg 5-day return | +0.58% |
| Avg 30-day return | -0.85% |
| Avg 90-day return | +0.67% |
| Best 30-day return | +10.02% |
Trading Pattern
InsiderAlpha's records for Steven B. Klinsky go back to 2024: 20 primary Form 4 filings, an average of 6.7 per year. The typical open-market purchase is $408K (68 buys totaling $27.72M). The largest single buy on record is $1.48M of NMFC in 2026. 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.
Career & Filing History
Every role Steven B. Klinsky has reported on a Form 4, reconstructed from the filings themselves - reporting insiders must state their relationship to the issuer (officer title, director seat, or 10% ownership) on every filing.
- Director, 10% Owner at New Mountain Finance Corp (NMFC) - 3 filings, 2026
- Director at New Mountain Finance Corp (NMFC) - 16 filings, 2024 to 2026
Recent Transactions
| Date | Ticker | Company | Code | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-03-12 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 184.2K | $8.05 | $1.48M |
| 2026-03-12 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 149.2K | $8.05 | $1.20M |
| 2026-03-12 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 92.1K | $8.05 | $741K |
| 2026-03-12 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 74.6K | $8.05 | $600K |
| 2026-03-06 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 158.6K | $8.10 | $1.28M |
| 2026-03-06 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 79.3K | $8.10 | $642K |
| 2026-03-05 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 124.6K | $8.17 | $1.02M |
| 2026-03-05 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 167.0K | $7.94 | $1.33M |
| 2026-03-05 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 62.3K | $8.17 | $509K |
| 2026-03-05 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 83.5K | $7.94 | $663K |
| 2026-03-03 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 124.5K | $7.79 | $969K |
| 2026-03-03 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 92.0K | $7.69 | $708K |
| 2026-03-03 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 62.2K | $7.79 | $485K |
| 2026-03-03 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 46.0K | $7.69 | $354K |
| 2025-09-18 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 85.4K | $9.78 | $835K |
| 2025-09-18 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 21.3K | $9.78 | $209K |
| 2024-12-19 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 48.2K | $11.28 | $544K |
| 2024-12-19 | NMFC | New Mountain Finance Corp | P - Open-market purchase | 24.1K | $11.28 | $272K |
| 2024-12-19 | - | New Mountain Private Credit Fund | P - Open-market purchase | 12.6K | - | |
| 2024-12-19 | - | New Mountain Private Credit Fund | P - Open-market purchase | 12.6K | - |
Most Active Insiders Right Now
Steven B. Klinsky has no recent co-filers at the same companies, so here are the insiders with the largest open-market activity across the market in the last 90 days.
- MetLife Investment Management, LLC - $1600000.00B of FINS open-market activity in the last 90 days
- Magnetar Financial LLC - $16357.48B of CRWV open-market activity in the last 90 days
- Marianne Okland - $18.46B of STNG open-market activity in the last 90 days
- VisionWave Holdings, Inc. - $14.13B of SVRE open-market activity in the last 90 days
- Vanessa Allen Sutherland - $7.44B of PSX open-market activity in the last 90 days
- AI Alpine (Luxembourg) S.a.r.l. - $2.69B of INIO open-market activity in the last 90 days
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
- Joseph Stilwell
- William P. Stiritz
- SUMITOMO MITSUI FINANCIAL GROUP, INC.
- Suva
- SUVRETTA CAPITAL MANAGEMENT, LLC
- Donald William Swanson
- Synchron
- Kevin Tang
Frequently Asked Questions
Who is Steven B. Klinsky?
Steven B. Klinsky holds the role of Director at New Mountain Finance Corp (NMFC). Klinsky's filing history also covers New Mountain Private Credit Fund. Klinsky has reported 20 insider filings with the SEC since 2024. The most recent filing was in March 2026.…
Has Steven B. Klinsky been buying or selling stock?
Recorded transactions: 68 open-market purchases ($27.72M) and 0 open-market sales across all tracked filings.
How accurate is Steven B. Klinsky's historical track record?
Across 64 tracked purchases, Steven B. Klinsky averaged -0.8% avg 30-day return with a 30% 30-day win rate. InsiderAlpha rates the track record at 2/5 stars.
Where can I see all of Steven B. Klinsky'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.
Learn More
Open the live Steven B. Klinsky profile on InsiderAlpha for real-time alerts, AI-scored trade ideas, and full transaction history.