The regulator has been asked to see whether competition is being distorted by a dominant firm. Under competition / antitrust principles, regulators normally look at:

Profits (A): persistently high profits may indicate market power or abuse of dominance.

Market shares (B): high and stable market share for one firm can signal dominance and lack of effective competition.

Prices across the industry (C): higher-than-expected or similar prices between competitors may indicate weak competition or collusion.

Entry barriers (E): high barriers (e.g. licences, regulation, capital intensity, brand strength) reduce competitive pressure and help a dominant firm maintain power.

Medical treatment efficacy (D) relates to quality of clinical outcomes, which is important for health regulators, but it is not primarily a competition issue, so it’s less relevant to whether the market is operating “fairly” in a competition sense.