OzForex (OFX) and GBST (GBT) have both had profit warnings - both are down 19% in a day. Aconex (ACX) fell 45% in a day on a profit warning earlier the same week. It is a $1.1bn stock (was $2bn). The alarm bells are ringing. In the same week, we have seen a 17.71% fall in Virtus (VRT) on another guidance downgrade. This followed warnings from Bellamy’s (BAL) and Sirtex (SRX), Brambles (BXB), Oroton (ORL), Servcorp (SRV), Aurizon (AZJ - deck clearing with write-downs - new CEO) and Pro-Pac Packaging (PPG.AX). I may have missed some others. Here is a bit of a guide to identifying stocks that have (1) the potential to fall a lot if they had a warning; and (2) are at risk of a profit downgrade. (VIEW LINK)