BLK vs SEIC
BlackRock, Inc. (BLK) and Sei Investments Co (SEIC) are both filed with the SEC under Security Brokers, Dealers & Flotation Companies. BLK is 13.5× SEIC's size by market cap ($180.9B against $13.4B); BLK trades at the higher fiscal-year P/E (33.1× against 19.8×); SEIC reports the higher net margin (31.1% against 22.9%); BLK grew sales faster over three years (+29.8% against +4.9%); and over the past year SEIC returned +27.2% against BLK's +5.2%.
| BLK | SEIC | |
|---|---|---|
| Last close | $1,164.48 | $111.63 |
| Market cap | $180.9B | $13.4B |
| P/E (FY) | 33.1× | 19.8× |
| P/S | 7.5× | 5.8× |
| EV/EBITDA | 22.3× | — |
| Gross margin | — | 35.2% |
| Operating margin | 29.1% | 27.3% |
| Net margin | 22.9% | 31.1% |
| Return on equity | 10.7% | 30.4% |
| Sales growth (3y) | +29.8% | +4.9% |
| EPS growth (3y) | +1.3% | +17.6% |
| Dividend yield | 1.7% | 0.9% |
| 1-year return | +5.2% | +27.2% |
Screener snapshot — prices as of 2026-08-28. Each side's last close is the most recent session the snapshot holds for that company, which can be an earlier one, and its 1-year return is measured to that close. Market caps struck on 2026-08-27. Last close, market cap and the 1-year return are price figures; every other row is computed over the company's latest filed fiscal year — FY2025 (ended 2025-12-31) for both. — not published for this company. A ratio goes unpublished for more than one reason: a component the calculation needs is not on file, the filing does not tag the line it is read from, or the calculation is not defined on the filed basis — EV/EBITDA is not printed on non-positive EBITDA, and return on equity is not computed on a zero or negative equity base.
Who holds them, and who has traded them
| BLK | SEIC | |
|---|---|---|
| Institutional holders (13F) | 2,307 | 563 |
| Insider buyers − sellers (180d) | -2 | -5 |
| Congressional trades disclosed (180d) | 6 | 0 |
| Executive-branch officials on file — trades disclosed (180d) | 9 | 0 |
Counts only. The congressional figures count transactions dated in the trailing 180 days and disclosed in STOCK Act periodic transaction reports; amounts are filed as ranges and are never summed. The executive-branch figures count the same window of transactions, and they are scoped to one roster. The officials OGE posts for direct download. Insider buyers − sellers counts distinct people filing open-market Form 4 purchases minus distinct people filing open-market sales over the trailing 180 days, capped at ±5.
BLK vs SEIC: common questions
- Is BLK bigger than SEIC?
- BLK carries the larger market cap — $180.9B against $13.4B, both struck on 2026-08-27.
- Which trades at a higher P/E, BLK or SEIC?
- BLK, at a fiscal-year 33.1× against 19.8× for SEIC. Both are price ÷ latest full-year diluted earnings per share, not a trailing-twelve-month P/E.
- How have BLK and SEIC performed over the past year?
- SEIC returned +27.2% and BLK +5.2%, measured on the trailing calendar year to the last close.
- How many institutions hold BLK and SEIC?
- 2,307 13F filers report a position in BLK and 563 in SEIC, on the latest quarter in the panel.
- Are BLK and SEIC in the same industry?
- Both are filed with the SEC under Security Brokers, Dealers & Flotation Companies, which is the classification this pairing is built on.
BLK overview → · SEIC overview → · BLK institutional ownership → · SEIC institutional ownership → · Congress and BLK → · Executive branch and BLK →
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Source: SPZCO — https://spzco.com/vs/blk-vs-seic