Shares of Allergan plc Ordinary Shares plunged more than 16 percent on Tuesday after the U.S. Treasury Department and Internal Revenue Service revamped their efforts to limit U.S.-based companies from participating in tax inversion deals. Waste Connections, Inc. , a U.S.-based integrated municipal solid waste services company that provides solid waste collection, announced earlier this year it plans on acquiring Progressive Waste Solutions Ltd , a Canada-based peer.