H. Income Tax

Effective Tax Rate

	Three Months Ended						Six Months Ended
	March 31,						March 31,
	2016			2015			2016			2015
	(Dollars in millions)						(Dollars in millions)
Provision for income taxes	$	11		$	14		$	6		$	17
Effective tax rate		20	%		36	%		12	%		18	%

During the three and six months ended March 31, 2016, the Company recorded tax provisions of $11 million and $6 million, resulting in effective tax rates of 20% and 12%, respectively. These amounts included a net discrete tax expense of $1 million and a net discrete tax benefit of $5 million, respectively, for the three and six months ended March 31, 2016. During the three and six months ended March 31, 2015, the Company recorded tax provisions of $14 million and $17 million, resulting in an effective tax rate of 36% and 18%, respectively. These amounts included a net discrete tax expense of $4 million and a net discrete tax benefit of $9 million, respectively, for the three and six months ended March 31, 2015.

Uncertainties

Cabot files U.S. federal and state and non-U.S. income tax returns in jurisdictions with varying statutes of limitations. The 2012 through 2015 tax years remain subject to examination by the United States Internal Revenue Service (“IRS”) and various tax years from 2005 through 2015 remain subject to examination by the respective state tax authorities. In significant non-U.S. jurisdictions, various tax years from 2004 through 2015 remain subject to examination by their respective tax authorities. Cabot’s significant non-U.S. jurisdictions include China, France, Germany, Italy, Japan, and the Netherlands.

Certain Cabot subsidiaries are under audit in jurisdictions outside of the U.S. In addition, certain statutes of limitations are scheduled to expire in the near future. It is reasonably possible that a change in the unrecognized tax benefits may also occur within the next twelve months related to the settlement of one or more of these audits, however, an estimated range of the impact on the unrecognized tax benefits cannot be quantified at this time.

During the three and six months ended March 31, 2016, Cabot released uncertain tax positions of $1 million and $3 million, respectively, due to the expirations of statutes of limitations in various jurisdictions. During the three and six months ended March 31, 2015, Cabot released uncertain tax positions of $1 million and $12 million, respectively, due to the expirations of statutes of limitations in various jurisdictions.