2026-09-22T10:12:11-05:00 2025-12-31 Foundation Source 3333 New Hyde Park Rd Ste 406 New Hyde Park NY 11042 990PF 2025-01-01 222777617 William & Karen Tell Foundation % Foundation Source WILL 8008391754 Foundation Source 501 Silverside Rd Wilmington DE 198091377 William Tell President 8008391754 2026-09-15 true Jeffrey D Haskell P01345770 8008391754 2025 X 5493287 X 0 X 13834 13834 55811 55811 152817 1493602 152817 222462 222462 115056 115056 34558 34558 42765 42765 6546 246 1155 1155 1230 1230 26483 191 26292 227793 43202 178291 97190 97190 324983 43202 275481 -102521 179260 0 377840 337907 337907 131684 150621 150195 2753955 2470723 4703497 97966 300173 301688 3361445 3259424 5493287 0 0 X 3361445 3259424 3361445 3259424 3361445 3259424 3361445 -102521 500 3259424 3259424 Publicly-traded Securities 1493602 1340785 152817 152817 152817 2492 2492 2492 3688 0 3688 X 0 1196 1196 0 false false false false false false false true true DE true false false false false true Foundation Source 8008391754 501 Silverside Road Suite 123 Wilmington DE 198091377 false false false false true false false false false false false false false false false false false false false false false false Caroline Tell Falk Foundation Source 501 Silverside Rd Wilmington DE 198091377 Dir, Chair, VP 20.0 36544 0 0 Katie Falk Foundation Source 501 Silverside Rd Wilmington DE 198091377 Dir, Sec 10.0 18272 10609 0 Karen Tell Foundation Source 501 Silverside Rd Wilmington DE 198091377 Dir, Treas 1.0 0 0 0 Madeleine W Tell Foundation Source 501 Silverside Rd Wilmington DE 198091377 Asst Sec, Dir 10.0 14560 5123 0 William F Tell Foundation Source 501 Silverside Rd Wilmington DE 198091377 Dir, Pres 30.0 45680 10176 0 5013438 347190 0 5360628 0 5360628 80409 5280219 264011 264011 2492 2492 261519 500 262019 262019 275481 0 0 0 0 275481 262019 2023 2022 2021 115673 109828 225501 275481 262019 13462 238963 0 115673 123290 109828 13462 Karen Tell X ACADEMY FOUNDATION 8949 WILSHIRE BLVD BEVERLY HILLS CA 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