That is not the farthest they can go.
SEC has revoked many symbols - I posted a link to four that were revoked in the same order.
Revocation doesn't leave a zombie stock, the ticker is delisted.
Delisting is the removal of a listed security from a stock exchange. The delisting of a security can be voluntary or involuntary and usually results when a company ceases operations, declares bankruptcy, merges, does not meet listing requirements, or seeks to become private.
Last year they revoked
Kevin Harrington (famous from As Seen On TV
and Shark tank
) and one of his investment companies were involved in that one.
And now Harrington and others are being sued
FYI I've already contacted the SEC about removing the revoked ORYN from my account. I called them after the brokerage refused to remove it. As I recall, they told me to ask the brokerage to have it removed. I explained that the brokerage said they couldn't remove it until ordered to do so by the SEC. I don't remember what they said to that, but I decided it was futile to continue trying.
I won't get any kind of write-off for it, but it does appear as an asset on financial paperwork I submit, even though it's worthless and doesn't exist anymore.