Logo of <a href="https://en.wikipedia.org/wiki/AT%26T_Corporation" class="extiw" title="en:AT&amp;T Corporation">AT&amp;T Corporation</a> designed by Saul Bass and introduced in 1983, 12-bar inverted version
AT&amp;T Corporation
<a rel="nofollow" class="external free" href="https://www.bellsystemmemorial.com/pdf/att_brand_guidelines.pdf">https://www.bellsystemmemorial.com/pdf/att_brand_guidelines.pdf</a>