OmniAb Heads Into Earnings With Shorts Retreating and Options Skewed Bullish

OABI enters its November 5 earnings report in an unusual spot: short sellers have been quietly cutting positions for two weeks while options traders show some of the most lopsided bullish skew of the past year.

The positioning story is the clearest angle this week. Short interest has fallen roughly 5% over the past month from a recent peak, dropping to 5.75% of the free float from a high of around 6.2% in mid-October. That retreat is notable given the 32% build in short interest over the prior month, which means some of the newer shorts are now being unwound into the stock's recovery. Borrow costs remain low at 0.57%, up around 21% on the week but still well inside territory that would suggest any meaningful squeeze pressure. Availability is wide open, around 842% of short interest, meaning there are roughly eight shares available to lend for every one already borrowed. The lending market is not under stress.

Options are telling a more interesting story. The put/call ratio has collapsed to 0.05, nearly 0.75 standard deviations below its 20-day average of 0.07, and sits well below its 52-week high of 0.13. Call open interest is swamping puts by a wide margin. That is an unusually one-sided setup heading into a catalyst, and it sits in contrast to the short interest picture: shorts are trimming, but options traders appear to be actively expressing upside. The ORTEX short score has drifted down to 49.4 from 53.5 two weeks ago, consistent with the short-side decompression.

The Street remains constructive but targets are spread wide. The two most recent analyst actions, both filed in early October, show Leerink Partners raising its target to $12 while maintaining Outperform, and StoneX lifting its target to $6 while keeping a Buy. The mean target across covering analysts sits at $8.33, against a current price of $5.11, implying around 63% nominal upside. HC Wainwright has maintained an $11 Buy for over a year. The bull case rests on OmniAb's royalty aggregation model, over 425 active programs with 98% carrying downstream economics, and an Eli Lilly collaboration with up to $370 million in milestones and tiered royalties. The bear case is structural: the company's economics depend heavily on partner assets clearing clinical and regulatory hurdles, and AI-based sequence generation is a growing competitive threat to animal-model discovery platforms. Factor scores offer little resolution. EPS momentum ranks in the 19th to 25th percentile across 30-day and 90-day windows. EPS surprise sits in the 16th percentile. The stock is loss-making, with a price-to-book of 1.6 and a deeply negative PE.

On ownership, the register carries a few large and recently active positions worth noting. Whitefort Capital is the top institutional holder at just over 7% of shares, but cut its position by nearly 4 million shares in the quarter ending June 30. Avista Capital trimmed sharply too, reducing by 5.8 million shares as of April. On the other side, Nomura added over 4.3 million shares to reach 3.5% of shares. BlackRock added around 790,000 shares in the September quarter. Robert Goldstein, listed separately in the 13D/G register, last disclosed a stake of 8.5% as of February 2026, up from 7.0% previously. Janus Henderson, which held 6.6% as recently as May 2025, filed an amended 13G in August 2025 showing its stake had fallen to 0.8%, consistent with the disclosure caveat that holders dropping below 5% may exit without further filings.

The one prior earnings data point in the snapshot is from October 2026, which showed a single-day move of minus 7.3% and a five-day move of minus 4.5%. With the next print five days away and options pricing in a strongly bullish tilt, the question heading into November 5 is whether the call-heavy options positioning reflects genuine conviction on the quarter or simply the absence of put protection in a thinly traded name.