The private equity-backed Houston firm Haymaker Minerals & Royalties has agreed to sell to Texas rival Kimbell Royalty Partners in a $404 million cash-and-stock deal. The five-year-old oil and gas royalties company in Houston is supported by major equity firms Kayne Anderson Capital Advisors and Kohlberg Kravis Roberts, known as KKR, which will acquire ownership stakes in Kimbell through the deal. The deal represents the further consolidation of energy companies growing in shale oil and gas plays in the U.S., especially in West Texas' booming Permian Basin.