MBB vs BKAG: Holdings Overlap
iShares · 11144 holdings · $39.1B · as of 2026-05-31
BNY Mellon · 5070 holdings · $2.2B · as of 2026-04-30
Holdings snapshots are 31 days apart (MBB: 2026-05-31, BKAG: 2026-04-30). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are MBB and BKAG?
iShares MBS ETF (MBB, by iShares) holds 11144 positions; BNY Mellon Core Bond ETF (BKAG, by BNY Mellon) holds 5070. They have 445 holdings in common, and by portfolio weight the two funds are 5.0% identical. In practical terms the pair is essentially distinct, holding almost none of the same securities.
- Overlap by Weight
- 5.0%Sum of the smaller weight of each shared holding
- Shared Holdings
- 445MBB holds 11144 · BKAG holds 5070
- Weight in Shared Holdings
- MBB 23%·BKAG 8%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in MBB
10699 of 11144 positions (75.3% of the fund) are not held by BKAG. Showing the top 30 by weight.
- Fannie Mae Pool0.52%
- Freddie Mac Pool0.50%
- Ginnie Mae0.46%
- Fannie Mae Pool0.44%
- Fannie Mae Pool0.44%
- Ginnie Mae II Pool0.41%
Only in BKAG
4625 of 5070 positions (91.0% of the fund) are not held by MBB. Showing the top 30 by weight.
- U.S. Treasury Notes/Bonds0.60%
- U.S. Treasury Notes0.56%
- U.S. Treasury Notes0.47%
- U.S. Treasury Notes0.46%
- U.S. Treasury Notes0.44%
- U.S. Treasury Notes0.43%
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| MBB | -0.2% | +0.4% | +3.9% | +4.7% | +0.3% | +1.2% | 4.33% |
| BKAG | -0.6% | -0.3% | +2.1% | +4.1% | -0.3% | — | 3.94% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in MBB vs BKAG →
Shared Holdings(445)
The top 10 shared positions account for 21% of the overlap, led by Ginnie Mae II Pool, Uniform Mortgage-Backed Securities and Government National Mortgage Association.
| Ginnie Mae II Pool | 0.15% | 0.13% | 0.13% |
|---|---|---|---|
| Uniform Mortgage-Backed Securities | 0.31% | 0.13% | 0.13% |
| Government National Mortgage Association | 0.53% | 0.13% | 0.13% |
| Uniform Mortgage-Backed Securities | 0.22% | 0.13% | 0.13% |
| FNMA/FHLMC UMBS, Single Family, 30 Year | 0.64% | 0.11% | 0.11% |
| Uniform Mortgage-Backed Securities | 0.09% | 0.20% | 0.09% |
| Government National Mortgage Association | 0.31% | 0.08% | 0.08% |
| Government National Mortgage Association | 0.55% | 0.08% | 0.08% |
| Ginnie Mae II Pool | 0.09% | 0.08% | 0.08% |
| G2-30YR-Multi | 0.67% | 0.08% | 0.08% |
| Government National Mortgage Association | 0.08% | 0.10% | 0.08% |
| Government National Mortgage Association | 0.28% | 0.07% | 0.07% |
| Freddie Mac Pool | 0.08% | 0.07% | 0.07% |
| Government National Mortgage Association | 0.06% | 0.08% | 0.06% |
| Ginnie Mae II Pool | 0.06% | 0.10% | 0.06% |
| Government National Mortgage Association | 0.06% | 0.09% | 0.06% |
| Uniform Mortgage-Backed Securities | 0.06% | 0.06% | 0.06% |
| Ginnie Mae II Pool | 0.05% | 0.14% | 0.05% |
| Uniform Mortgage-Backed Securities | 0.05% | 0.07% | 0.05% |
| Fannie Mae Pool | 0.05% | 0.28% | 0.05% |
| Government National Mortgage Association | 0.10% | 0.05% | 0.05% |
| Government National Mortgage Association | 0.17% | 0.05% | 0.05% |
| Uniform Mortgage-Backed Securities | 0.06% | 0.05% | 0.05% |
| Uniform Mortgage-Backed Securities | 0.09% | 0.05% | 0.05% |
| Uniform Mortgage-Backed Securities | 0.10% | 0.05% | 0.05% |
Showing the top 250 of 445 shared holdings by overlap weight.
Frequently Asked Questions
How much do MBB and BKAG overlap?
MBB and BKAG overlap by 5.0% of portfolio weight. They share 445 holdings (MBB holds 11144 positions and BKAG holds 5070), based on each fund's latest SEC-reported holdings.
Is it redundant to own both MBB and BKAG?
The two portfolios are 5.0% identical by weight. Owning both is genuine diversification: the funds hold almost none of the same securities.
What are the biggest shared holdings of MBB and BKAG?
The largest positions held by both funds are Ginnie Mae II Pool, Uniform Mortgage-Backed Securities, Government National Mortgage Association, Uniform Mortgage-Backed Securities and FNMA/FHLMC UMBS, Single Family, 30 Year. Together the top 10 shared positions account for 21% of the total overlap.
What does MBB own that BKAG doesn't?
10699 positions (75.3% of MBB) are unique to MBB, led by Fannie Mae Pool, Freddie Mac Pool and Ginnie Mae. In the other direction, 4625 positions (91.0% of BKAG) are unique to BKAG.