Exxon Mobil announced on Thursday it would pay almost $1.7 billion to acquire two privately held Pennsylvania energy companies to add to its natural gas reserves in the Marcellus Shale, Bloomberg reports.

Exxon Mobil is the latest energy giant to expand its natural gas holdings by investing in shale, a formation of sedimentary rock that companies hope to extract gas from through a controversial process called fracking.

The acquisitions of Warrendale, Pa.-based Phillips Resources and its affiliate, Butler, Pa.-based TWP Inc., will help Exxon Mobil almost double its Marcellus Shale holdings to 707,000 net acres, according to the Oil & Gas Financial Journal.

Read the full article, "Reed Smith, K&L Gates Lead on Exxon Mobil's Marcellus Shale Buy," at amlawdaily.com.