13. Segment and Geographic Information

The Company has two operating business segments: electronic brokerage and market making. These segments are supported by the corporate segment, which provides centralized services and executes the Company’s currency diversification strategy.

The Company conducts its electronic brokerage business through certain Interactive Brokers subsidiaries, which provide electronic trade execution and clearing services to customers worldwide. The Company conducts its remaining market making business (see Note 2 – Discontinued Operations and Costs Associated with Exit or Disposal Cost) principally through its Timber Hill subsidiaries on some of the world’s leading exchanges and market centers, primarily in exchange‑traded equities, equity options and equity‑index options and futures.

Significant transactions and balances between the Operating Companies occur, primarily as a result of certain Operating Companies holding exchange or clearing organization memberships, which are utilized to provide execution and clearing services to affiliates. Charges for transactions between segments are designed to approximate full costs. Intra‑segment and intra‑region income and expenses and related balances have been eliminated in this segment and geographic information to reflect the external business conducted in each segment or geographic region. Corporate items include non‑allocated corporate income and expenses that are not attributed to segments for performance measurement, net gains and losses on positions held as part of the Company’s overall currency diversification strategy, corporate assets and eliminations.

Management believes that the following information by business segment provides a reasonable representation of each segment’s contribution to total net revenues and income before income taxes for the years ended December 31, 2017, 2016, and 2015, and total assets as of December 31, 2017, 2016, and 2015:



	Year-Ended December 31,
	2017		2016		2015
	(in millions)
Net revenues
Electronic brokerage	$	1,405	$	1,239	$	1,097
Market making		86		190		298
Corporate		211		(33)		(206)
Total net revenues	$	1,702	$	1,396	$	1,189
Income before income taxes
Electronic brokerage	$	860	$	756	$	536
Market making		(27)		44		130
Corporate		216		(39)		(208)
Total income before income taxes	$	1,049	$	761	$	458



	December 31,
	2017		2016		2015

	(in millions)
Segment assets
Electronic brokerage	$	58,787	$	50,072	$	44,421
Market making		8,469		11,765		10,825
Corporate		(6,094)		(7,164)		(6,512)
Total assets	$	61,162	$	54,673	$	48,734

The Company operates its automated global business in the U.S. and international markets on more than 120 electronic exchanges and market centers. A significant portion of the Company’s net revenues are generated by subsidiaries operating outside the U.S. International operations are comprised of electronic brokerage and market making activities in 25 countries in Europe, Asia and the Americas (outside the U.S.). The following table presents total net revenues and income before income taxes by geographic area for the years ended December 31, 2017, 2016, and 2015. The geographic analysis presented below is based on the location of the subsidiaries in which the transactions are recorded. This geographic information does not reflect the way the Company’s business is managed.



	Year-Ended December 31,
	2017		2016		2015
	(in millions)
Net revenues
United States	$	1,393	$	1,046	$	832
International		309		350		357
Total net revenues	$	1,702	$	1,396	$	1,189
Income before income taxes
United States	$	947	$	632	$	294
International		102		129		164
Total income before income taxes	$	1,049	$	761	$	458