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Data center campus · 400 S. LaSalle St., Chicago (Loop), Cook County, Illinois

400 S. LaSalle data center conversion

Under construction as of Sept. 16, 2026

Conversion of the six-story former Cboe headquarters in the Loop into a 33 MW data center by Legacy Investing and GI Partners. Also known as: former Cboe headquarters.

Cite← Illinois data centers
Adams CountyAlexander CountyBond CountyBoone CountyBrown CountyBureau CountyCalhoun CountyCarroll CountyCass CountyChampaign CountyChristian CountyClark CountyClay CountyClinton CountyColes CountyCook CountyCrawford CountyCumberland CountyDe Witt CountyDeKalb CountyDouglas CountyDuPage CountyEdgar CountyEdwards CountyEffingham CountyFayette CountyFord CountyFranklin CountyFulton CountyGallatin CountyGreene CountyGrundy CountyHamilton CountyHancock CountyHardin CountyHenderson CountyHenry CountyIroquois CountyJackson CountyJasper CountyJefferson CountyJersey CountyJo Daviess CountyJohnson CountyKane CountyKankakee CountyKendall CountyKnox CountyLake CountyLaSalle CountyLawrence CountyLee CountyLivingston CountyLogan CountyMacon CountyMacoupin CountyMadison CountyMarion CountyMarshall CountyMason CountyMassac CountyMcDonough CountyMcHenry CountyMcLean CountyMenard CountyMercer CountyMonroe CountyMontgomery CountyMorgan CountyMoultrie CountyOgle CountyPeoria CountyPerry CountyPiatt CountyPike CountyPope CountyPulaski CountyPutnam CountyRandolph CountyRichland CountyRock Island CountySaline CountySangamon CountySchuyler CountyScott CountyShelby CountySt. Clair CountyStark CountyStephenson CountyTazewell CountyUnion CountyVermilion CountyWabash CountyWarren CountyWashington CountyWayne CountyWhite CountyWhiteside CountyWill CountyWilliamson CountyWinnebago CountyWoodford County400 S. LaSalle data center conversion · Under construction · 33 MW
Power33MW reported · stated
Floor area300,500sq ft

Who is behind it

Project400 S. LaSalle data center conversionAlso: former Cboe headquarters
Developer and teamLegacy Investing
GI Partners
End userNot found in the recordsNot yet named in any record or credited report we have found.

The record, newest first

  1. A second conversion permit, declared at $151.1 million, was issued. (GrayStak Media (Substack), Oct. 15, 2026; Colocation Scout (powered by Bridgepointe Technologies), Oct. 15, 2026)

  2. Chicago issued a building permit for a conversion phase declared at $51.1 million. (GrayStak Media (Substack), Oct. 15, 2026; Colocation Scout (powered by Bridgepointe Technologies), Oct. 15, 2026)

  3. Legacy Investing and GI Partners announced a 33 MW conversion of the 300,500-square-foot building, aiming for more than 20 MW in service by early 2027. (Data Center Dynamics, Nov. 17, 2025)

  4. A Legacy Investing affiliate bought the former Cboe building for $40 million, according to Cook County records cited by the Sun-Times. (Chicago Sun-Times, Nov. 7, 2025)

Conflicts and open questions

  • Under 50 MW; kept because it is under construction and confirmed.
  • Permit details come from secondary compilations of city permit data; the city permit records themselves were not opened.
  • Coordinates approximate, from the 400 S. LaSalle St. address.

The full record

Status note
City building permits for conversion phases were issued July 6 and Sept. 16, 2026.
Power note
Developer figure; not stated whether IT or utility capacity. More than 20 MW targeted for service by early 2027.
Evidence
News reports; primary records not yet obtained
Size class
Under 50 MW (outside main scope; kept for completeness)
Map position approximate, from the reported address or area. Updated Oct. 17, 2026.