Market on Open order gives me a worse price than daily open

Alpaca Trading
1

Hi! I’ve been happy with alpaca data and trading services in general. Today I tried market on open order with real trading account, specifically on symbol “PACB”, however, I’m really confused at the execution price I got:

Execution price: 1.5900 (SELL)
Open price from alpaca daily data: 1.61
Open price in yahoo finance: 1.59 (Pacific Biosciences of California, Inc. (PACB) Stock Price, News, Quote & History - Yahoo Finance)
Open price in google: 1.61

Apparantly, if the “real” open price is 1.61, then the market on open order doesn’t give me a fair price as promised? which price should I trust in general?

Thank you.

2

@PatL If you are trading in an Alpaca paper account, Market On Open (MOO) orders are simulated as regular market orders and execute at the opening quote (ie buy orders fill at the ask and sell orders fill at the bid). While the paper trade environment generally simulates live trading quite well this is one notable difference. In live trading MOO orders fill at the listing exchange opening auction price.

Was this a paper or live trade execution?

3

Hi @Dan_Whitnable_Alpaca thanks for looking into it, I am aware paper account isn’t real moo order. So I use real money account.

4

Found a similar post OPG orders not filled at open price (live trading)

I think this answers my question.