The bid price of any security is the highest price that someone is willing to pay for that security.  The ask price of any security is the lowest price that someone is willing to sell that security.  The “theo”, “mark” or “mid” price is simply the bid plus the offer divided by two.

Click the video below as I explain the nuances between these measures.

Follow me on Twitter @MikeShorrCbot

about the author:

Mike Shorr

Since 1994, Michael has been an on-the-floor market maker, Vice-President of Interest Rate Derivatives for Knight Financial Products and Director of Education and Options Instructor at Trading Advantage. He makes the oftentimes complex world of options and trading accessible to the novice and advanced trader alike. Michael has a Bachelor of Science degree in Statistics and Finance from the University of Illinois Champaign-Urbana. He presently is Director, Trader Education at ProsperTradingAcademy.

Read Similar Articles

May 1, 2026

Buying Puts vs Selling Calls: What’s The Difference?

When traders expect a stock to drop, options give them more than one way to potentially profit from that move. Two of the most common bearish options strategies traders use in these situations are buying puts and selling calls. When presented with both options, some traders might ask: “If they’re both bearish options trades, aren’t […]

Read Article
February 15, 2026

Why Option Premiums Rise Before Binary Events

Ever wonder why option premiums rise before binary events in the stock market? It’s not uncommon for option prices to spike ahead of major announcements like: For context, I like to describe option premium as the difference between the contract’s price and intrinsic value. It’s essentially what buyers pay for the “hope” that an option […]

Read Article
February 6, 2026

The Delta Greek: How To Measure Option Premium

When the markets move, the Delta Greek can be one of the most valuable metrics to options traders. There’s a particular correlation between the Delta Greek and options premium that can help traders find out how much the price of an option is expected to change. From my personal experience, I believe this pattern can […]

Read Article

Read Similar Articles

https://www.prospertrading.com/how-scotts-amzn-earnings-trade-went-down/How Scott’s AMZN Earnings Trade Went Down
April 30, 2026

How Scott’s AMZN Earnings Trade Went Down

Scott Bauer has had Amazon Inc. (AMZN) on his radar all week, and pulled the trigger on an AMZN earnings trade that paid off big time. On Wednesday, Scott laid out an example trade for AMZN on the Schwab Network — hours before they reported earnings: Amazon smashed earnings expectations, and made some wild moves […]

Read Article
https://www.prospertrading.com/scotts-example-trade-plays-both-sides-of-amazon-earnings/Scott’s Example Trade Plays Both Sides Of Amazon Earnings
April 29, 2026

Scott’s Example Trade Plays Both Sides Of Amazon Earnings

Amazon Inc. (AMZN) reported earnings today and beat expectations. Both metrics smashed expectations for $1.63 EPS and $177 billion revenue. Scott Bauer had Amazon on his radar ahead of today’s report. He highlighted it this week on MarketMinds, and covered the stock on Sunday’s Weekly Earnings Prep. Today on the Schwab Network, he laid out […]

Read Article
https://www.prospertrading.com/the-big-move-scott-calculated-in-amazon-stock/The Big Move Scott Calculated In Amazon Stock
April 27, 2026

The Big Move Scott Calculated In Amazon Stock

Amazon stock has had a wild year. It’s up over 15% in 2026 — and nearly 31% in the last month! It’s one of five Mag 7 stocks that report earnings this week, and among four that reveal their quarterly results on Wednesday, April 29. Scott Bauer loves Amazon stock, and has it on his […]

Read Article