Grammar doubt: what am I bid for that old book?

[Aresende]

I read in Longman Dictionary the follow question as an example of “bid” usage: “what am I bid for that old book?” (= what price people will offer me for it). I’d like to know what the tense of the verb “bid” in this case. I thought that the correct form would be: “what am I bidding…” Can anyone help me, please?

Thanks!

[Jamie (K)]

When an auctioneer says, "What am I bid..." the sentence is in the passive voice, and "bid" is in the passive participle.

Active: "The auction participant bid me $300 for the clock." ("Me" is the indirect object.)
Passive: "I was bid $300 for the clock."

Compare these:

Active: "Someone gave me an important letter." ("Me" is the indirect object.)
Passive: "I was given an important letter."

[Aresende]

Perfect explanation, Jamie. Thank you very much and happy new year!