I suspect the short thesis on DDR was a macro one i.e. there is...

I suspect the short thesis on DDR was a macro one i.e. there is a microchip shortage globally which they speculate will impact DDR. Shorters clearly didnt do their homework on what a truly exceptional business DDR is and what a mistake taking a short position would be. You could also reasonably argue DDR is overvalued, after all it just purchased a competitor for around 4.5x EBITDA whereas DDR trades on closer to 20x EBITDA.

Also important to note those short numbers have a 4 day lag so they would currently be reflecting the position at market close on Tuesday. The acquisition was announced last Monday so there will have been 2 days worth of short covering as at the latest short reporting date (T-4 / last Tuesday).