Abbott Short Interest Jumps 23% in a Week, But Borrow Stays Loose

Short sellers added to positions in Abbott Laboratories at an unusual pace this week, even as the stock held broadly flat and the borrow market remained among the easiest in the sector.

The short interest build is the standout number. Shares short rose 23% over the past week, from around 13.3 million to 16.7 million, pushing the SI % of free float to roughly 0.96%. That weekly move is approximately three standard deviations above Abbott's typical weekly shift over the past year, making it statistically unusual even though the absolute level remains low. The surge follows a sharp unwind through mid-October, when short interest had collapsed from above 20 million shares in late September to the low 13 millions, so some of this week's build looks like a partial rebuild rather than a fresh directional call. Borrow costs tell a similar story: cost to borrow at 0.38% is down nearly 10% on the week and well off the brief spike above 1.4% seen on 1 October. With borrow availability at maximum, there is no sign of any squeeze dynamic in the lending pool.

The Street picture after Q3 results is one of maintained conviction but trimmed expectations. Eighteen analysts carry buy-equivalent ratings against five holds, and no sells. Post-earnings target moves ran in two directions simultaneously: Wells Fargo lifted its target to $120, Baird raised to $123, while JPMorgan, Citigroup, RBC, TD Cowen and BTIG all lowered targets, mostly into the $118 to $125 range. The net effect is a consensus that still sees roughly 15 to 20% upside from current levels near $103, but with the distribution tightening lower. One notable exception came on 27 October, when Argus Research downgraded to Hold from Buy without publishing a price target, a directional signal to watch even if the firm is not a typical bellwether. The bull case centres on the planned Nutrition separation, a formulary win for Libre Duo effective January 2027, and a valuation near ten-year lows at roughly 17 times 2027 EPS. Bears point to the EP growth guidance cut, from roughly 25% to roughly 20% for Q4, driven by Amulet 360 order timing and broader left atrial appendage closure market softness, alongside FX drag and a lower 2027 revenue baseline.

The peer comparison sharpens the post-earnings context. Abbott gained 0.6% on the week, roughly in line with the peer median. BDX matched that at plus 0.6%, STE outperformed at plus 1.5%, and MDT and SYK both dipped. Abbott is holding its own within the group, but the post-print underperformance noted in Tuesday's note, when MDT and SYK rallied while Abbott slipped, reflects a market still processing the guidance revision. The ORTEX factor scores add a layer of nuance: the analyst recommendation differential ranks in the 98th percentile, confirming the Street skew heavily toward buy. Short score at 28.8 and improving availability rank (81st percentile) reinforce the picture of a name with limited bearish conviction despite this week's SI build.

One structural event worth tracking sits further out. ORTEX puts a 60% probability on Abbott's share count in the Russell 1000 and Russell 3000 declining as a result of the planned Nutrition spinoff. The estimated announcement date is 26 December 2027, with an effective date of 31 December 2027. These dates are estimated, not confirmed by the index provider. The spinoff itself was announced on 21 October 2026 and has been covered in recent ORTEX corporate action notes. The index mechanics mean index-tracking funds would need to adjust positions in both the Abbott stub and the new nutrition entity at that point, though no tracker trade is expected before then.

The unusual pace of short interest rebuilding this week, set against still-loose borrow conditions and a firmly buy-skewed Street, is the data combination worth watching as Abbott trades through the post-earnings period ahead of the Nutrition separation.