Blackrock MuniHoldings California Quality Fund, Inc. (MUC)
MUC moved a median of -0.02% 30 minutes after news, and +0.05% by the close. How MUC actually reacts to news — the realized, point-in-time move the market made, measured across 59 labeled events over the last three years with zero look-ahead.
MUC’s median reaction, across the day.
| Horizon | Median | % positive | Events |
|---|---|---|---|
| 5-min | 0.00% | 32% | 53 |
| 30-min | -0.02% | 41% | 59 |
| 60-min | 0.00% | 46% | 59 |
| to close | +0.05% | 56% | 59 |
| Middle 50% of MUC reactions | -0.16% to +0.05% |
|---|---|
| Median reaction (30-min) | -0.02% |
| Measured reactions | 59 |
Half of all Blackrock MuniHoldings California Quality Fund, Inc. news events land between -0.16% and +0.05% at 30 minutes.
Reaction stats as of 2026-09-21. Newest measured event . Reaction = percent move vs. the price at the news timestamp.
Email me when MUC moves on news.
One email per qualifying move — the headline, the measured reaction, and how it compares to MUC's baseline. Nothing else.
Recent MUC events, each with its measured reaction.
| Date | Headline | Event | Source | 5-min | To close |
|---|---|---|---|---|---|
| Form N-CEN BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CEN | SEC EDGAR | -0.10% | -0.57% | |
| Form N-CSR BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CSR | SEC EDGAR | +0.10% | +0.68% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form NPORT-P | SEC EDGAR | +0.05% | -0.35% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Sep 10 | SEC filing · Form N-23C-2 | SEC EDGAR | -0.58% | -0.77% | |
| Form N-PX BLACKROCK MUNIHOLDINGS For: Jun 30 | SEC filing · Form N-PX | SEC EDGAR | -0.09% | +0.14% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Apr 30 | SEC filing · Form NPORT-P | SEC EDGAR | +0.05% | +0.05% | |
| Form N-CSRS BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form N-CSRS | SEC EDGAR | +0.00% | +0.29% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form NPORT-P | SEC EDGAR | -0.05% | -0.67% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Feb 27 | SEC filing · Form N-23C-2 | SEC EDGAR | +0.00% | +1.01% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Oct 31 | SEC filing · Form NPORT-P | SEC EDGAR | — | +0.14% | |
| Form DEFA14A BLACKROCK MUNIHOLDINGS | SEC filing · Form DEFA14A | SEC EDGAR | +0.00% | +0.14% | |
| Form N-CEN BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CEN | SEC EDGAR | — | +0.05% | |
| Form DEFA14A BLACKROCK MUNIHOLDINGS | SEC filing · Form DEFA14A | SEC EDGAR | -0.09% | -0.74% | |
| Form N-CSR BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CSR | SEC EDGAR | +0.00% | -0.92% | |
| Form DEFA14A BLACKROCK MUNIHOLDINGS | SEC filing · Form DEFA14A | SEC EDGAR | +0.00% | -0.37% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form NPORT-P | SEC EDGAR | +0.00% | -0.37% | |
| Form DEFA14A BLACKROCK MUNIHOLDINGS | SEC filing · Form DEFA14A | SEC EDGAR | +0.18% | -0.46% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Sep 11 | SEC filing · Form N-23C-2 | SEC EDGAR | — | +0.00% | |
| Form EFFECT BLACKROCK MUNIHOLDINGS | SEC filing · Form EFFECT | SEC EDGAR | -0.29% | +0.19% | |
| Form N-14 8C/A BLACKROCK MUNIHOLDINGS | SEC filing · Form N-14 | SEC EDGAR | -0.19% | +0.00% | |
| Form N-PX BLACKROCK MUNIHOLDINGS For: Jun 30 | SEC filing · Form N-PX | SEC EDGAR | -0.15% | +0.20% | |
| Form N-14 8C BLACKROCK MUNIHOLDINGS | SEC filing · Form N-14 | SEC EDGAR | +0.00% | +0.10% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Apr 30 | SEC filing · Form NPORT-P | SEC EDGAR | — | +0.39% | |
| Form DEFA14A BLACKROCK MUNIHOLDINGS | SEC filing · Form DEFA14A | SEC EDGAR | +0.00% | -0.19% | |
| Form N-CSRS BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form N-CSRS | SEC EDGAR | -0.43% | +0.05% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form NPORT-P | SEC EDGAR | -0.01% | +0.42% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Oct 01 | SEC filing · Form N-23C-2 | SEC EDGAR | — | +0.63% | |
| Form N-CEN/A BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CEN | SEC EDGAR | +0.00% | -0.09% | |
| Form 8-K BLACKROCK MUNIHOLDINGS For: Jan 20 | SEC filing · Form 8-K | SEC EDGAR | +0.09% | +0.37% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Oct 31 | SEC filing · Form NPORT-P | SEC EDGAR | +0.05% | -0.47% | |
| Form N-CEN BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CEN | SEC EDGAR | +0.00% | -0.09% | |
| Form N-CSR BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form N-CSR | SEC EDGAR | +0.00% | -0.09% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jul 31 | SEC filing · Form NPORT-P | SEC EDGAR | -0.04% | +0.04% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Sep 12 | SEC filing · Form N-23C-2 | SEC EDGAR | +0.00% | +0.26% | |
| Form N-PX BLACKROCK MUNIHOLDINGS For: Jun 30 | SEC filing · Form N-PX | SEC EDGAR | +0.07% | -0.11% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Aug 26 | SEC filing · Form N-23C-2 | SEC EDGAR | +0.04% | +0.04% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Apr 30 | SEC filing · Form NPORT-P | SEC EDGAR | +0.09% | -0.45% | |
| BlackRock Announces Management Fee Waiver for Certain Closed-End Funds | Press release | Business Wire | +0.09% | -0.18% | |
| Form N-CSRS BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form N-CSRS | SEC EDGAR | +0.05% | +0.14% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Jan 31 | SEC filing · Form NPORT-P | SEC EDGAR | — | +0.32% | |
| Form N-23C-2 BLACKROCK MUNIHOLDINGS For: Mar 01 | SEC filing · Form N-23C-2 | SEC EDGAR | +0.14% | +0.27% | |
| Form NPORT-P BLACKROCK MUNIHOLDINGS For: Oct 31 | SEC filing · Form NPORT-P | SEC EDGAR | +0.13% | +0.14% |
Each reaction is the move the market actually made, measured from the news timestamp. Headlines link through to the MUC section they belong to.
Where else MUC is measured.
MUC earnings → · Analyst actions → · SEC filings →
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How the numbers are made.
How is Blackrock MuniHoldings California Quality Fund, Inc.'s median reaction calculated?
Every labeled MUC news event is measured from its own timestamp: the last trade before the news is the base price, and the move is read at fixed horizons — 30 minutes of trading, then the close. The median across 59 events is what this page reports. Point-in-time, zero look-ahead: no event borrows information from a later one.
What counts as a positive reaction?
Any event whose price move is above zero at the horizon, relative to the last trade before the news timestamp. 41% of MUC's measured events are up at 30 minutes; the rest close the window flat or negative.
How often is this page updated?
The news table refreshes automatically as new events are labeled and priced. The reaction medians are re-pulled in batches from the dataset — the figures here are as of 2026-09-21.
Does MUC's past reaction predict its next one?
No. These are realized facts about past events, not forecasts. They describe a distribution — they say nothing certain about any future move.