Related party transactions

3 Months Ended

Mar. 31, 2017

Our significant related party transactions occurring during the three months ended March 31, 2017 and 2016 are described below. We believe that all of the transactions with our related parties were on terms that approximate market.

Glencore ownership

As of March 31, 2017, Glencore plc and its affiliates (together "Glencore") owned 42.9% of Century’s outstanding common stock (47.5% on a fully-diluted basis assuming the conversion of all of the Series A Convertible Preferred Stock) and all of our outstanding Series A Convertible Preferred Stock. From time to time Century and Glencore enter into various transactions for the purchase and sale of primary aluminum, purchase and sale of alumina, tolling agreements and certain forward financial contracts.

Sales to Glencore

For the three months ended March 31, 2017 and 2016 we derived approximately 77% and 88%, respectively, of our consolidated sales from Glencore.

Glencore purchased aluminum produced at our North American smelters during 2016 under a purchase and sale agreement, effective as of December 31, 2014 (the "2015-2016 US Sales Agreement"). The 2015-2016 US Sales Agreement expired on December 31, 2016. We have since entered into a new agreement with Glencore pursuant to which Glencore has agreed to purchase aluminum produced at our North American smelters in 2017. The pricing for aluminum sold under these agreements is determined by reference to the Midwest Transaction Price plus additional negotiated product premiums.

We have also entered into an agreement with Glencore pursuant to which Glencore has agreed to purchase substantially all of the primary aluminum produced at Grundartangi through 2017 at prices based on the LME price for primary aluminum plus the European Duty Paid premium and any applicable product premiums.

Glencore purchases the aluminum we produce for resale.

Purchases from Glencore

We purchase alumina from Glencore under a long-term supply agreement and on a spot basis. Pursuant to our current agreement, Glencore has agreed to supply us with alumina through 2017 at prices indexed to the LME price of primary aluminum. In 2016 and 2017, upon mutual agreement, all of our purchases from Glencore under this agreement were priced based on a published alumina index.

Financial contracts with Glencore

During 2017, we entered into certain financial contracts with Glencore. Refer to Note 15 Derivatives to the consolidated financial statements included herein.

Transactions with Baise Haohai Carbon Co., Ltd. ("BHH")

We own a 40% stake in BHH, a joint venture that owns a carbon anode and cathode facility located in the Guangxi Zhuang Autonomous Region of south China. We have an agreement with BHH to provide carbon anodes to Grundartangi through December 31, 2017.

Summary

A summary of the aforementioned significant related party transactions for the three months ended March 31, 2017 and 2016 is as follows:



	Three months ended March 31,
	2017		2016
Net sales to Glencore	$	280,573	$	280,377
Purchases from Glencore	71,581		44,013
Purchases from BHH	2,780		2,383