Facing mounting criticism from islanders and local lawmakers, Facebook CEO Mark Zuckerberg on Friday revealed he was dropping his legal gambit to force the sale of land tracts on his seafront property on the island of Kauai that are claimed by native Hawaiians. "Upon reflection, I regret that I did not take the time to fully understand the quiet title process and its history before we moved ahead," Zuckerberg wrote in Kauai newspaper The Garden Island. Zuckerberg had previously tried to secure parcels of land within the property by filing quiet title actions, a legal mechanism used to establish ownership and force a sale of land where inheritance rights stretch back generations and formal documentation is lacking.