SPDR Series Trust - State Street SPDR Portfolio Mortgage Backed Bond ETF
US ˙ ARCA

SecuritySPMB / SPDR Series Trust - State Street SPDR Portfolio Mortgage Backed Bond ETF
InstitutionAssetmark, Inc
Latest Disclosed Ownership1,813,363 shares
Latest Disclosed Value $ 40,601,197
Assetmark, Inc reports 4.10% increase in ownership of SPMB / SPDR Series Trust - State Street SPDR Portfolio Mortgage Backed Bond ETF

On May 6, 2026 - Assetmark, Inc filed a 13F-HR form disclosing ownership of 1,813,363 shares of SPDR Series Trust - State Street SPDR Portfolio Mortgage Backed Bond ETF (US:SPMB) valued at $40,601,198 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 23, 2026 disclosing 1,741,982 shares of SPDR Series Trust - State Street SPDR Portfolio Mortgage Backed Bond ETF. This represents a change in shares of 4.10% during the quarter. The current value of the position is $40,220,391 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-06 2026-03-31 13F SPDR SERIES TRUST STATE STREET SPD 78464A383 1,813,363 71,381 4.10 40,601 3.98 0.0828
2026-01-23 2025-12-31 13F SPDR SERIES TRUST STATE STREET SPD 78464A383 1,741,982 83,017 5.00 39,047 4.89 0.0796
2025-11-06 2025-09-30 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,658,965 94,186 6.02 37,227 7.65 0.0798
2025-08-04 2025-06-30 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,564,779 48,546 3.20 34,582 3.44 0.0816
2025-05-06 2025-03-31 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,516,233 64,477 4.44 33,433 6.86 0.0918
2025-02-06 2024-12-31 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,451,756 -3,814 -0.26 31,285 -4.60 0.0850
2024-11-01 2024-09-30 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,455,570 4,422 0.30 32,794 4.77 0.0939
2024-08-13 2024-06-30 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,451,148 28,565 2.01 31,301 1.30 0.0968
2024-05-07 2024-03-31 13F SPDR SER TR PORT MTG BK ETF 78464A383 1,422,583 1,422,583 30,899 0.1005
2023-02-10 2022-12-31 13F SPDR SER TR PORT MTG BK ETF 78464A383 0 -480,751 -100.00 0 -100.00
2022-11-01 2022-09-30 13F SPDR SER TR PORT MTG BK ETF 78464A383 480,751 -16,816 -3.38 10,312 -9.30 0.0482
2022-08-03 2022-06-30 13F SPDR SER TR PORT MTG BK ETF PORT MTG BK ETF 78464A383 497,567 17,057 3.55 11,369 -1.25 0.0510
2022-05-13 2022-03-31 13F SPDR SER TR PORTFLI MORTGAGE PORTFLI MORTGAGE 78464A383 480,510 49,882 11.58 11,513 5.34 0.0482
2022-02-14 2021-12-31 13F SPDR SER TR PORTFLI MORTGAGE PORTFLI MORTGAGE 78464A383 430,628 18,954 4.60 10,929 3.22 0.0449
2021-11-12 2021-09-30 13F SPDR SER TR PORTFLI MORTGAGE ETF 78464A383 411,674 26,009 6.74 10,588 6.17 0.0474
2021-08-16 2021-06-30 13F SPDR SER TR PORTFLI MORTGAGE ETF 78464A383 385,665 385,665 9,973 0.0462
2020-11-13 2020-09-30 13F SPDR SER TR PORTFLI MORTGAGE ETF 78464A383 0 -8 -100.00 0 -100.00 0.0000
2020-08-11 2020-06-30 13F SPDR SER TR PORTFLI MORTGAGE ETF 78464A383 8 0 0.00 0 0.0000
2020-05-12 2020-03-31 13F SPDR SER TR PORTFLI MORTGAGE ETF 78464A383 8 0 0.00 0 0.0000
2020-02-11 2019-12-31 13F SPDR SERIES TRUST PORTFLI MORTGAGE ETF 78464A383 8 0 0.00 0 0.0000
2019-11-13 2019-09-30 13F SPDR SERIES TRUST PORTFLI MORTGAGE ETF 78464A383 8 0 0.00 0 0.0000
2019-08-14 2019-06-30 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 8 0 0.00 0 0.0000
2019-05-14 2019-03-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 8 -244,310 -100.00 0 -100.00
2019-02-13 2018-12-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 244,318 37,236 17.98 6,208 18.90 0.0599
2018-11-13 2018-09-30 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 207,082 883 0.43 5,221 -0.15 0.0475
2018-08-01 2018-06-30 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 206,199 2,861 1.41 5,229 0.25 0.0514
2018-05-16 2018-03-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 203,338 16,335 8.74 5,216 7.19 0.0540
2018-02-13 2017-12-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 187,003 7,763 4.33 4,866 3.12 0.0501
2017-11-08 2017-09-30 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 179,240 -7,068 -3.79 4,719 -3.65 0.0537
2017-08-14 2017-06-30 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 186,308 -46,432 -19.95 4,898 -20.05 0.0616
2017-09-15 2017-03-31 13F/A-1 SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 232,740 -79,174 -25.38 6,126 -25.27 0.0805
2017-05-08 2017-03-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 232,740 -79,174 6,126
2017-09-15 2016-12-31 13F/A-1 SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 311,914 -8,346 -2.61 8,197 -5.81 0.1204
2017-02-14 2016-12-31 13F SPDR SERIES TRUST BLOMBRG BRC MRTG ETF 78464A383 311,914 -8,346 8,197
2017-09-14 2016-09-30 13F/A-1 SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 320,260 -2,065 -0.64 8,703 -0.87 0.1324
2016-11-04 2016-09-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 320,260 -2,065 8,703
2017-09-14 2016-06-30 13F/A-1 SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 322,325 34,486 11.98 8,779 12.18 0.1476
2016-08-08 2016-06-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 322,325 34,486 8,779
2017-09-14 2016-03-31 13F/A-1 SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 287,839 20,506 7.67 7,826 9.15 0.1366
2016-05-13 2016-03-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 287,839 20,506 7,826
2017-09-14 2015-12-31 13F/A-1 SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 267,333 34,563 14.85 7,170 13.68 0.1329
2016-02-12 2015-12-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 267,333 34,563 7,170
2016-01-05 2015-09-30 13F/A-1 SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 232,770 35,303 17.88 6,307 18.96 0.1316
2015-11-10 2015-09-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 232,770 6,307
2015-08-13 2015-06-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 197,467 51,375 35.17 5,302 32.19 0.1104
2015-05-12 2015-03-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 146,092 146,092 -26.02 4,011 -24.35 0.0854
2015-02-03 2014-12-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 0 -112,421 -100.00 0 -100.00
2014-11-10 2014-09-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 112,421 5,006 4.66 3,059 3.98 0.0707
2014-08-12 2014-06-30 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 107,415 15,841 17.30 2,942 19.40 0.0627
2014-05-06 2014-03-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 91,574 83,205 994.20 2,464 1,009.91 0.0601
2014-02-11 2013-12-31 13F SPDR SERIES TRUST BRC MTG BCKD BD ETF 78464A383 8,369 8,369 222 0.0053
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.