The financial performance of our operating segments and reconciliation to consolidated operating loss is as follows (in thousands): Three months ended September 30, Nine months ended September 30, 2018 2017 2018 2017 Segment Revenue: Marketplaces $ 24,712 $ 22,493 $ 65,334 $ 56,061 Media 16,744 10,967 44,189 33,202 Total revenue $ 41,456 $ 33,460 $ 109,523 $ 89,263 Segment Operating Expenses: Marketplaces (1) $ 24,386 $ 22,869 $ 65,498 $ 59,584 Media (1) 10,185 6,188 25,636 20,410 Add: Corporate expenses (2) 6,774 6,290 20,363 19,812 Consolidated operating expenses $ 41,345 $ 35,347 $ 111,497 $ 99,806 Segment Operating Contribution: Marketplaces (3) $ 326 $ (376) $ (164) $ (3,523) Media (3) 6,559 4,779 18,553 12,792 Add (deduct): Corporate expenses (2) (6,774) (6,290) (20,363) (19,812) Acquisition, disposition and realignment costs (4) 17  241 299 Adjusted EBITDA (5) $ 128 $ (1,887) $ (1,733) $ (10,244) Reconciliation to consolidated pre-tax income (loss): Adjusted EBITDA (5) $ 128 $ (1,887) $ (1,733) $ (10,244) Add (deduct): Interest income (expense), net 114 64 160 143 Other (expense) income, net (59) (6) (92) (9) Depreciation and amortization (6) (2,687) (2,749) (7,588) (8,815) Stock-based compensation (7) (2,502) (2,182) (7,386) (6,426) Acquisition, disposition, realignment and contingent payment costs (8) (1,016)  (1,555) (299) Loss before income taxes $ (6,022) $ (6,760) $ (18,194) $ (25,650) (1) Segment operating expenses reflects operating expenses that are directly attributable to the operating segment, not including corporate and unallocated expenses, and also excluding the following: (a) depreciation expense; (b) amortization of intangible assets; (c) share-based compensation expense; (d) interest and other income (expense); (e) income taxes; and (f) contingent payments to certain key employees/equity holders of acquired businesses. (2) Corporate expenses include operating expenses that are not directly attributable to the operating segments, including: corporate information technology, marketing, and general and administrative support functions and also excludes the following: (a) depreciation expense; (b) amortization of intangible assets; (c) share-based compensation expense; (d) interest and other income (expense); and (e) income taxes. (3) Segment operating contribution reflects segment revenue less segment operating expenses. Operating contribution has certain limitations in that it does not take into account the impact to the statement of operations of certain expenses and is not directly comparable to similar measures used by other companies. (4) Represents such items, when applicable, as (a) legal, accounting and other professional service fees directly attributable to acquisition, disposition or corporate realignment activities, (b) employee severance, and (c) other payments attributable to acquisition, disposition or corporate realignment activities, excluding contingent payments to certain key employees/equity holders of acquired businesses. (5) Adjusted EBITDA reflects net income (loss) excluding interest (income) expense, income tax expense (benefit), and certain other non-cash or non-recurring items impacting net income (loss) from time to time, principally comprised of depreciation and amortization, stock-based compensation, contingent payments to certain key employees/equity holders of acquired businesses and other payments attributable to acquisition, disposition or corporate realignment activities. (6) Represents depreciation expense of our long-lived tangible assets and amortization expense of our finite-lived intangible assets, including amortization expense related to our investment in media content assets, included in our GAAP results of operations. (7) Represents the expense related to stock-based awards granted to employees as included in our GAAP results of operations. (8) Represents such items, when applicable, as (a) legal, accounting and other professional service fees directly attributable to acquisition, disposition or corporate realignment activities, (b) employee severance, (c) contingent payments to certain key employees/equity holders of acquired businesses and (d) other payments attributable to acquisition, disposition or corporate realignment activities.