If Commander Shepard elected to save the original Council during Saren's assault on the Citadel in 2183, Tiron expresses great admiration towards Shepard and is cordial. Shepard can record an advertisement for Tiron, gaining a discount; he also says that he would name his first-born after Shepard if asked to. Alternatively, Tiron can be persuaded to sponsor Shepard's mission in the Terminus Systems -- happy to support anyone hunting mercenaries and geth, Tiron gives the Commander a discount.
If Shepard let the original Council perish, Tiron is visibly angry at Shepard and snipes the Commander for being prejudiced against alien species. With some persuasion, however, Shepard can convince the resentful turian to give them a discount by impressing him with their ability to kill the 'scum' of the Terminus Systems. However, there is a caveat: Tiron will deny the existence of the discount if anyone asks.