This has been slightly edited based on the feedback in this thread.
Tier 0 - Binance and Coinbase -
Tier 1 - major, reputable, well-established exchanges -
Reputable as defined in Bitwise report. Bitwise classifies the 10 exchanges as real volume exchanges or reference exchanges. The 10 exchanges include Binance, Bitfinex, bitFlyer, Bitstamp, Bittrex, Coinbase Pro, Gemini, itBit, Kraken and Poloniex.
The bounty to be valid for at least 6 months from the initial approval. After that period - the ability to cancel or reduce the amount because of the price swings and other justifiable reasons (subject to vote).
Previous discussion here: PROPOSAL: bounty for getting PNK listed on exchanges