BlackRock Model Portfolios Rebalance: Why Active Core Now Has Momentum

by Todd Rosenbluth of VettaFi, 9/29/26

momentum-active-core

The BlackRock Model Portfolio Solutions team made significant allocation shifts during the week ended September 24, 2026. The team recently managed over $300 billion and often causes shockwaves in the ETF industry. Last week’s activity drove notable net outflows from the iShares Innovation and Tech Active ETF (BAI), the iShares Defense Industrials Active ETF (IDEF), and the iShares MSCI USA Momentum Factor ETF (MTUM).

Concurrently, BlackRock’s models led advisors to redirect money into the iShares Large Cap Core Active ETF (BLCR). This underscores a strategic preference for active ETFs, particularly highly diversified core equity exposures.

Key Takeaways

  • Broadening Equity Exposure: BlackRock’s $300 billion-plus model portfolio team made US equity allocation changes in late September.
  • Active Core Equity ETF Inflows: BLCR pulled in a sizable $2.2 billion net inflow last week, proving the demand for diversified active core exposure.
  • Momentum No Longer in Favor: MTUM experienced a $4.5 billion net outflow last week as the momentum factor was pared back.

From Fixed Income Adjustments to Equity Realignment

A few times a year, BlackRock makes a model allocation change. When completed, this causes iShares ETFs to climb and fall from the flows leaderboard.

In late May 2026, the little known iShares Global Government Bond USD Hedged Active ETF (GGOV) was in focus. The ETF went from $45 million to nearly $3 billion in a week as BlackRock shifted its fixed income allocations.

By contrast, September’s adjustments featured many changes to U.S. equity exposure. In March 2026, BLCR managed just over $100 million. Today the active equity ETF has $9 billion thanks to large allocations six months ago and more recently. The equity ETF gathered $2.2 billion over five days last week.

Inside BLCR’s Diversified Active Strategy

In 2026, there has been growing demand for active large-cap strategies focused on security selection. Many large-cap index ETFs have mega-cap technology companies dominating the top positions, In contrast, BLCR’s portfolio managers use fundamental and quantitative research to balance growth drivers with resilient value:

  • Growth & AI Leaders: BLCR captures technology upside through core holdings in mega-caps like Microsoft and NVIDIA.
  • Broadened Value: Rather than being too heavily exposed to tech, BLCR provides high exposure to other sectors. These include healthcare leader Cardinal Health and industrial distributor WESCO International.
  • Strong Performance in 2026: Year to date through late September, BLCR rose 17.1%, outperforming the 13.4% gain for the S&P 500 Index.