SAN FRANCISCO (Reuters Breakingviews) - What kind of potential punishment would keep noses clean in Silicon Valley? As companies like Alphabet, Amazon.com, Apple and Facebook get bigger and attract more attention from watchdogs, it’s a pressing question. The nearly $350 billion of cash that those four firms have means the prospect of fines no longer carries much sting. Wall Street holds some lessons on potent alternatives. Financial penalties have been the main way regulators have hit Big Tech. The largest one has been the $5 billion fine imposed on Facebook in 2019 for mishandling user data. The company also had to set up a new privacy committee and implement other reforms. But it didn’t seriously dent its cash pile, which totaled nearly $56 billion at the end of the third quarter. Wall Street has faced giant fines too. In October, Goldman Sachs agreed to pay more than $3 billion for its role in Malaysia’s 1MDB bribery scandal. But those levies barely move share prices these days. David Solomon’s bank also activated its own creative deterrent: pay cuts and clawbacks amounting to $174 million from Solomon, former boss Lloyd Blankfein and others. Clawbacks would work on the west coast too, where U.S. regulators like the Federal Trade Commission are poring over the way technology giants have treated customers and competitors. Tech executives may not get the jumbo payouts that bank bosses do, but they often have even more power, because of multi-class stock structures that allow co-founders to control a majority of shareholder votes. Financial regulators also have other tools. The Federal Reserve can curb banks’ buybacks and dividends, and this year stopped share repurchases for about three dozen firms to conserve capital. Granted, capital isn’t an issue at tech companies. But restricting buybacks for wrongdoing would be a powerful motivator. Facebook, Google, Apple and Amazon have authorized nearly $323 billion in stock repurchases over the last five years, according to Refinitiv data. There’s another leaf to be taken from bank watchdogs: save the toughest rules for the biggest companies. Lenders with fewer than $250 billion of assets get a lighter touch. For tech, the threshold could be 100 million users. That would net big firms but spare smaller ones like review site Yelp. Like Wall Street, these measures won’t ensure tech executives are always good, but they will make it less tempting to be bad. - This is a Breakingviews prediction for 2021. To see more of our predictions, click here