After enduring a week of attacks by Carl C. Icahn about his tenure on the board of eBay, the technology investor Marc Andreessen has delivered his most direct response yet to the hedge fund manager’s criticisms.

In a post on the blog of his venture capital firm, Andreessen Horowitz, Mr. Andreessen defended his conduct as an eBay director. Though he never mentioned Mr. Icahn by name, Mr. Andreessen reiterated that he had behaved properly at all times, including by recusing himself in discussions where he might have a conflict of interest.

“I disclose any situation where I believe I may have a potential conflict and recuse myself from any eBay board deliberation when I believe I may have a potential conflict due to an investment in another company,” Mr. Andreessen wrote.

While Mr. Andreessen spoke to The Wall Street Journal last week, he offered the newspaper a more indirect defense of his time as an eBay director. This time, he confronted head on the matter of Skype. His firm was part of a group that bought majority control of the online video service from eBay in 2009, a move Mr. Icahn contends deprived shareholders of a potentially bigger payout.

In the post, Mr. Andreessen reiterated that he fully disclosed his conflicts and recused himself from all discussions within the board about what eBay should do with Skype.

Here are the two main points he made about the deal:

* EBay’s retained ownership in the Skype spinoff was 30% vs. Andreessen Horowitz’s approximately 3%. That much larger ownership gave eBay a far bigger role in decision making on Skype after the spinoff than Andreessen Horowitz, as well as a far bigger economic payoff on the sale to Microsoft.

* Subsequent to the Skype transaction, I was re-elected to the eBay board in 2012 with virtually unanimous support – 99.7% of votes – of eBay shareholders. The Skype transaction received a high degree of public scrutiny when it happened; all of the facts around my role in the Skype transaction were fully public at that time; eBay has a very sophisticated body of shareholders; and if any of them saw any problem with my conduct around the Skype transaction, I am confident that they would have brought it up by 2012.

Mr. Andreessen batted away notions that the technology sector was likely to run into conflicts because of its rapid reconfiguration, with companies constantly buying each other. But to him, the matter is no different than when conglomerates gobbled up smaller companies in the 1980s.

He ended his post with an oblique swipe at Mr. Icahn.

Some people have also floated a theory that venture capitalists are more prone to potential conflicts than other kinds of directors due to their investments in multiple companies at once. I also don’t think that’s true. For example, activist hedge fund managers also tend to hold equity stakes in many companies at the same time, creating the exact same kind of potential conflict.

Your move, Mr. Icahn.