--- title: "AB Core Bond ETF trails AGG in its first year" url: "https://etf.net/news/ab-core-bond-etf-trails-agg-2026-11-09" published_at: "2026-11-09T15:50:24.365Z" updated_at: "2026-11-09T15:50:24.365Z" byline: "ETF.net Research" --- # AB Core Bond ETF trails AGG in its first year The share price fell 4.4% as the 10-year Treasury yield rose, and a holder who did not reinvest the payouts finished 0.78 percentage points behind iShares' aggregate-bond ETF. By ETF.net Research. Published Nov 9, 2026. A year after AllianceBernstein converted an institutional bond fund into the AB Core Bond ETF CORB, a holder who took the payouts in cash and did not reinvest them finished 0.78 percentage points behind the same stake in BlackRock's iShares Core U.S. Aggregate Bond ETF AGG. Treasury yields rose, the share price fell, and the distributions covered most of that drop. Noel Archard, AllianceBernstein's global head of ETFs and portfolio solutions, called it "a product with a proven track record" the morning trading began, in the firm's [launch announcement](https://alliancebernsteinholdinglp.gcs-web.com/news-releases/news-release-details/alliancebernstein-enhances-etf-offerings-two-new-fixed-income). The conversion closed on Nov. 7, 2025, and Bernstein Intermediate Duration Institutional Portfolio became CORB. The fund's [semi-annual shareholder report](https://www.sec.gov/Archives/edgar/data/1496608/000119312526332052/d66642dncsrs.htm) shows $854 million of net assets and 28.47 million shares at that moment. At those figures the new shares were worth $30 each. From a first close of $30.05 on Nov. 10, 2025, the shares finished at $28.74 on Nov. 6, 2026, down 4.4%. The 10-year Treasury yield rose from 4.13% on that first trading day to 4.86% on Nov. 6, 2026, an increase of 73 basis points. Chart: The 10-year yield **rose** from 4.13% to 4.86% in CORB's first year ## The benchmark CORB chose AllianceBernstein launched CORB as an actively managed fund, not an index fund. AGG tracks the Bloomberg U.S. Aggregate Bond Index, and CORB's own [summary prospectus](https://www.sec.gov/Archives/edgar/data/1496608/000119312526132591/d254600d497k.htm), dated March 31, 2026, names that same index as its benchmark. The mutual fund it replaced was called Intermediate Duration. The prospectus says the ETF will keep duration between 75% and 125% of that benchmark's under normal market conditions, which is why AGG is the comparison despite the old name. The objective in that prospectus is safety of principal and a moderate to high rate of current income. Over the year the fund paid the income, and the principal shrank with the share price. ## What a cash holder earned CORB paid $1.186 a share in distributions from Dec. 1, 2025 through Nov. 2, 2026. The share price fell $1.31 from the first close to Nov. 6, 2026. Adding that cash to the price change, and not assuming the payouts were reinvested, a buyer at $30.05 was down **0.41%**. A $10,000 stake became $9,959. Counted the same way, AGG came out ahead. It paid $3.98 a share over those same dates. Its price fell 3.6%, or $3.61, from $100.16 on Nov. 10, 2025 to $96.55 on Nov. 6, 2026, and that holder was up **0.37%**. A $10,000 stake became $10,037. The gap between those two results is **0.78** percentage points. CORB charges 0.28% a year, its prospectus says. AGG charges 0.03%, [iShares' summary prospectus](https://www.sec.gov/Archives/edgar/data/1100663/000119312526287958/d128878d497k.htm) dated June 29, 2026 says. The difference in fees is 0.25 percentage points, and the shortfall was about three times that extra charge. ## A lower fee than the mutual fund The mutual fund reached 0.45% only after a waiver. Before the conversion, an [information statement](https://www.sec.gov/Archives/edgar/data/1496608/000091957425004356/d30420d497.htm) dated Aug. 1, 2025 put the predecessor's expenses at 0.52% of assets before that waiver and 0.45% after it, for the fiscal year ended Sept. 30, 2024. The same filing set the ETF at 0.28%, with no waiver, and the prospectus still shows that rate. ## Near the value of the bonds Net asset value is the value of the bonds, per share. On Nov. 6, 2026 the shares closed at $28.74, two cents above the $28.72 net asset value AllianceBernstein reported for the day. The 30-day median bid-ask spread, the gap between what a buyer pays and what a seller receives, was 0.04% as of that date, the firm says on its [product page](https://www.alliancebernstein.com/us/en-us/investments/products/etf/fixed-income/ab-core-bond-etf.-.00039J756.html). ## The 10-year record The record Archard pointed to was mostly the mutual fund's. For the 10 years through Dec. 31, 2025, the predecessor's institutional shares returned 2.28% a year, against 2.01% for the Bloomberg U.S. Aggregate Bond Index, the summary prospectus says. Those returns were not adjusted for the ETF's lower fee, and the index itself charges nothing. A year on the exchange, measured against AGG rather than that fee-free index, has not extended the lead. One year of rising yields is a narrow test of a bond fund, and it is the only test this listing has had. Source: etf.net, https://etf.net/news/ab-core-bond-etf-trails-agg-2026-11-09. Please cite the page URL.