I think you've been lucky. My 26-year technology career has been evenly split between a full-time employee and consulting roles in New Jersey, all with Fortune 500 companies in either pharmaceutical or financial services industries.

A majority of the employee roles have required that I get permission to speak publicly about topics in my field (information security) with the caveat that I must present a disclaimer that my presentation does not represent my employer. In some cases, my presentation needed to be reviewed by the employer.

In the past, I have introduced myself as "employed by a Fortune 500 company with a blue logo".

Only one of my employers was in the technology field.

Here's an example from one former employer's handbook.

You should also consider potential conflicts with BMS business interests before agreeing to serve as a director, officer or other responsible position for an outside business; seeking a political or other government position; or engaging in service with a charitable, civic, religious, educational, public, political, or social organization. Where there is even a potential appearance of conflict, seek guidance and approval consistent with BMS policy.

As an independent consultant, none of those constraints can be placed on me without implicating New Jersey employment law.