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Private company

Ameritech

Logo: Ameritech, Public domain, via Wikimedia Commons3

Subsidiary of AT&T

AT&T Teleholdings, Inc., formerly known as Ameritech Corporation (and, before that, American Information Technologies Corporation), was an American telecommunications company that arose out of the 1984 AT&T divestiture. Ameritech was one of the seven Regional Bell Operating Companies created following the breakup of the Bell System. Ameritech was acquired in 1999 by SBC Communications, which subsequently acquired AT&T Corporation in 2006, becoming the present-day AT&T.2 It is headquartered in Chicago.1 Wikipedia text CC BY-SA 4.0

Last updated Oct 21, 2026.

Overview

1983Founded1
  • Industrytelecommunications1
  • HeadquartersChicago1

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AT&T Teleholdings, Inc., formerly known as Ameritech Corporation (and, before that, American Information Technologies Corporation), was an American telecommunications company that arose out of the 1984 AT&T divestiture. Ameritech was one of the seven Regional Bell Operating Companies created following the breakup of the Bell System. Ameritech was acquired in 1999 by SBC Communications, which subsequently acquired AT&T Corporation in 2006, becoming the present-day AT&T.2

Corporate structure

Ameritech sits at the top of its group. 2 entities, 1 country on record. Switch between the flow chart and the network, and select any entity to see its details.

Built from subsidiaries, stakes and holdings from Wikidata (CC0); major holders from Schedules 13D and 13G. Each entity in the chart links to its source.

What it owns

What Ameritech reports owning in its annual reports to the SEC: buildings, land and equipment, real estate and locations, investments, intangible assets and inventory, at the end of its latest fiscal year and a year before.

Stakes and holdings (Wikidata)

Things Wikidata records the company as owning, with the share when stated.1

Products and brands

  • telephone

Listed on Wikidata.1

Subsidiaries and ownership

Also owns

From Wikidata.1

Acquisitions

  1. 1986Acquired Massachusetts Computer Associates1

In May 1998, Ameritech announced its intent to merge with SBC Communications for $62 billion. This brought great concern to Federal and state regulators, who in turn did not approve the merger until SBC and Ameritech agreed to several conditions to ensure adequate competition. Most notably, regulators required:

that the merged company offer local phone service in thirty markets outside of its home territory within thirty months of the merger (i.e. by April 2002) or pay a $1.18B penalty

and that Ameritech Cellular assets in Chicago be sold to GTE in 1999, which later merged with Bell Atlantic to form Verizon in June 2000. Since SBC already had a majority stake in a large mobile provider (Cellular One), the merged company, if it were to operate Ameritech Cellular and Cellular One both in the same market, would have wielded too much market power.

On October 6, 1999, the Federal Communications Commission (FCC) approved the merger between SBC and Ameritech, then the two companies officially merged on October 8, 1999. Prior to the merger, Ameritech's Chairman and CEO was Richard Notebaert, who later (in 2002) became CEO of competitor Qwest.

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The end of the Ameritech name

On January 15, 2003, SBC Communications changed its d.b.a. names, changed the legal name of Ameritech Corp. to SBC Teleholdings, Inc., which began doing business as SBC Midwest. On January 15, 2006, d.b.a names were again changed to align with SBC's assumption of the AT&T brand identity following its acquisition of AT&T Corp. the previous year, and Ameritech was again renamed, becoming AT&T Teleholdings, Inc. and began doing business as AT&T Midwest.

Several Ameritech subsidiaries remain legally named "Ameritech", such as Ameritech Advanced Services; however, they do business as "AT&T Advanced Solutions".

In 2006, the holding companies Pacific Telesis and Southern New England Telecommunications were legally merged into AT&T Teleholdings. The company then became a holding company for Pacific Bell (and its subsidiary Nevada Bell) and Southern New England Telephone.

From Wikipedia’s article on Ameritech, shared under CC BY-SA 4.0.4

Timeline

  1. 1983Founded Founded1

Sources

The numbers on this page point here. Each one links to the record it came from.

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