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v3.25.4

Segments and Geographic Information - Operating Results By Segment (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 27, 2025 USD ($) segment | Dec. 28, 2024 USD ($) | Dec. 30, 2023 USD ($)
Segment Reporting [Abstract] |  |  |
Number of reportable segments | segment | 2 |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | $ 784,993 | $ 763,599 | $ 663,102
Cost of revenues | 476,142 | 455,676 | 404,522
Gross profit | $ 308,851 | $ 307,923 | $ 258,580
Gross margin | 39.30% | 40.30% | 39.00%
Research and development | $ 115,682 | $ 121,938 | $ 115,765
Selling | 51,299 | 53,538 | 52,519
Marketing | 18,909 | 21,079 | 22,623
Net contribution | 122,961 | 111,368 | 67,673
General and administrative | 62,866 | 67,169 | 57,870
Gain on sale of business | 0 | 20,581 | 72,953
Operating income | 57,070 | 64,780 | 82,756
Interest income | 10,640 | 14,111 | 7,217
Interest expense | (521) | (418) | (421)
Other income (expense), net | 2,202 | 939 | (285)
Income before income taxes and equity investment | 69,391 | 79,412 | 89,267
Factory start-up costs | 3,025 | 0 | 0
Probe Cards |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 637,898 | 625,960 | 497,903
Systems |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 147,095 | 137,639 |
Operating Segments | Probe Cards |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 637,898 | 625,960 | 497,903
Cost of revenues | 379,398 | 366,953 | 312,511
Gross profit | $ 258,500 | $ 259,007 | $ 185,392
Gross margin | 40.50% | 41.40% | 37.20%
Research and development | $ 86,295 | $ 90,463 | $ 83,104
Selling | 29,085 | 31,462 | 26,912
Marketing | 6,494 | 8,775 | 5,983
Net contribution | 136,626 | 128,307 | 69,393
Operating Segments | Systems |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 147,095 | 137,639 | 165,199
Cost of revenues | 85,542 | 78,128 | 80,464
Gross profit | $ 61,553 | $ 59,511 | $ 84,735
Gross margin | 41.80% | 43.20% | 51.30%
Research and development | $ 18,816 | $ 20,617 | $ 21,487
Selling | 14,938 | 16,082 | 17,026
Marketing | 7,472 | 7,184 | 9,367
Net contribution | 20,327 | 15,628 | 36,855
Corporate and Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues | 0 | 0 | 0
Cost of revenues | 11,202 | 10,595 | 11,547
Gross profit | (11,202) | (10,595) | (11,547)
Research and development | 10,571 | 10,858 | 11,174
Selling | 7,276 | 5,994 | 8,581
Marketing | 4,943 | 5,120 | 7,273
Net contribution | $ (33,992) | $ (32,567) | $ (38,575)

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