In afternoon trade, the S&P/ASX 200 Index (ASX: XJO) is on course to record a decent gain. At the time of writing, the benchmark index is up 0.45% to 7,715.6 points.

Four ASX shares that have failed to follow the market higher today are listed below. Here's why they are dropping:

Block Inc (ASX: SQ2)

The Block share price is down 2.5% to $88.47. Investors have been selling this payments company's shares after a mixed night for its NYSE-listed shares on Wall Street. This latest decline means that Black's shares are down approximately 22% since the start of the year.

DroneShield Ltd (ASX: DRO)

The DroneShield share price is down 5% to 97.5 cents. This is despite there being no news out of the counter drone technology company. However, Droneshield's shares have been under significant pressure recently amid concerns over its valuation. So much so, its shares have now lost an astonishing 64% of their value since peaking at $2.72 in the middle of last month. Despite this, they remain up 200% on a 12-month basis. It is also worth noting that Bell Popper currently has a hold rating on its shares but with a price target of $1.60. This is notably higher than current levels.

Integrated Research Limited (ASX: IRI)

The Integrated Research share price is down 7% to 76 cents. This morning, this user experience and performance management solutions provider announced that it has found its new CEO. The company has appointed Ian Lowe to the role, effective 1 October. The release notes that Lowe brings a wealth of experience and a proven track record of success in building and consolidating high-growth technology businesses. Chairman, Peter Lloyd, said: "Ian's appointment as CEO signifies a new era of leadership and growth for Integrated Research, and the Board looks forward to working closely with him to drive the Company's strategic vision and returning the Company to a path of value generation for its stakeholders."

Strike Energy Ltd (ASX: STX)

The Strike Energy share price is down 4% to 18.2 cents. This follows the release of an update on the drilling of Booth-1 in L7 in the north Perth Basin. According to the release, the L7 operator, Triangle Energy Global Ltd (ASX: TEG), has informed Strike that Booth-1 has reached Total Depth today with no moveable hydrocarbons discovered in any of the reservoir targets. In light of this, the Booth-1 well will be plugged and abandoned over the coming days.