Bank-owned homes and those in some stage of the foreclosure process saw their share of overall US home sales grow to 26% in the first quarter. The increase was driven by a spike in short sales, or homes that sell for less than what the owner owed on their mortgage, foreclosure listing firm RealtyTrac Inc. said today. Short sales make up the vast majority of homes sold while still in the foreclosure process. Those that aren’t sold or auctioned off typically end up being repossessed by banks, what most people commonly think of as foreclosures. In the first quarter, short sales grew 25% from a year earlier, hitting a three-year high.