Incorrect. It simply means you have more espionage points (EPs) than that civ. Hover over the name and you will see a ratio. The first number is their amount of points, the second number is your amount of points. If the ratio is in your favor the icon is present, indicating that you are "besting" them when it comes to espionage at that time.
(This does not mean, however, that you have more gold allocated to espionage at that time. It's possible that that civ could over-take you on the next turn, if they are spending more than you.)
To see how many EPs you need for passive missions, you have to go into the espionage screen (Ctrl+E) and click the appropriate civ's leaderhead on the left. You can then see how many EPs you would need, at that time, to benefit from passive missions. If you have a spy in their territory you will also see the cost for active missions.
Note that these costs will change over time depending on how much your rival is spending, and how long your spy has been in position (for active missions.) It's also possible, of course, that your costs could triple if the enemy performs a counter-espionage mission in your territory.