Segment Information
The Partnership has one operating segment, which is the Partnership's reportable segment, OpCo. The operating results of the segment are reviewed by the Partnership's Chief Executive Officer, the chief operating decision maker ("CODM"). The CODM evaluates segment performance based on net income. The CODM reviews the OpCo segment's actual net income trends to allocate resources and assess performance.
The OpCo segment's operations consist of two ethylene production facilities in Lake Charles, Louisiana, one ethylene production facility in Calvert City, Kentucky and a 200-mile common carrier ethylene pipeline that runs from Mont Belvieu, Texas to Longview, Texas. OpCo derives substantially all of its revenue from these production facilities primarily by selling ethylene to Westlake and others, as well as through the sale of co-products of ethylene production, including propylene, crude butadiene, pyrolysis gasoline and hydrogen. All of the OpCo segment's operations are located and conducted in the United States. All of the OpCo segment's sales are attributed to the United States.
Sales to Westlake accounted for more than 10% of sales in the OpCo segment, totaling $1,033,276, $950,801 and $1,026,655 for the years ended December 31, 2025, 2024 and 2023, respectively. Consolidated net sales and provision for income taxes as disclosed in the consolidated statements of operations and depreciation and amortization and additions to property, plant and equipment as disclosed in the consolidated statements of cash flows are fully attributed to the OpCo segment, and as such, separate OpCo segment amounts are not repeated in the tables below.
The accounting policies of the OpCo segment are the same as those described in Note 1.
Year Ended December 31,
202520242023
Significant segment expenses and other segment items
OpCo
Raw material, energy, manufacturing and logistics costs
$690,869 $605,058 $693,129 
Depreciation and amortization127,978 111,899 110,203 
Total cost of sales818,847 716,957 803,332 
Selling, general and administrative expenses24,853 24,699 26,217 
Other segment items (1)
(582)(3,005)(1,786)
Interest expense—Westlake
OpCo$1,316 $1,410 $1,496 
Corporate21,583 24,291 25,005 
$22,899 $25,701 $26,501 
Net income
OpCo$323,577 $397,245 $363,028 
A reconciliation of total segment net income to consolidated net income is as follows:
Year Ended December 31,
202520242023
Net income from OpCo
$323,577 $397,245 $363,028 
Corporate net loss
(25,001)(28,086)(28,402)
Net income
$298,576 $369,159 $334,626 
December 31,
20252024
Total assets
OpCo
$1,222,123 $1,238,420 
Corporate
34,410 49,536 
$1,256,533 $1,287,956 

_____________________________
(1)Other segment items includes interest expense—Westlake, other income, net and provision for income taxes.

Historical Timeline

Fiscal YearFiled
2025Mar 4, 2026Showing above
2024Mar 5, 2025

About Segments Disclosures

Segment disclosures break a company into its reportable operating units, revealing revenue, profit, and asset allocation that consolidated financial statements obscure. Under ASC 280, segments must match how the chief operating decision maker views the business, providing a window into internal management structure and resource allocation priorities.

Key signals: compare segment margins to identify which units drive profitability and which destroy value. Watch for changes in the number of reportable segments — segment aggregation or disaggregation often coincides with strategic shifts or attempts to obscure declining performance. Intersegment elimination patterns reveal internal pricing practices. The reconciliation between segment totals and consolidated figures exposes corporate overhead allocation and unallocated items. Geographic revenue concentration highlights regulatory and currency exposure. Compare segment-level capital expenditure against segment revenue to assess where management is investing for future growth versus harvesting existing assets.