CM002 · Capital Markets

Market Manipulation

Market manipulation is the artificial distortion of a security's price or volume to create a false or misleading impression of supply, demand, or price, so a position can be exited — or a benchmark can be gamed — at an advantage. The finding is a convergence finding: it lives in how large the price move is relative to the instrument's normal volatility, how concentrated the account's footprint is against total market volume, whether the trading is coordinated across linked accounts, and how much of the price move reverses once the manipulative window closes — the tell that the move was not information-driven.

Article 12 of the EU Market Abuse Regulation (MAR) defines market manipulation. Article 15 prohibits it outright. CM002 detects the trading-side signature of both.

Risk indicators

Price Impact Ratio

• Price move materially larger than the instrument's normal volatility
• Move concentrated in a short surveillance window rather than a sustained trend
• Move inconsistent with any contemporaneous public news or disclosure

Volume Concentration

• Account share of total market volume disproportionate to its normal trading pattern
• Volume concentrated in a thin or illiquid instrument
• Order flow inconsistent with the account's stated trading mandate

Coordinated Accounts

• Multiple accounts trading in concert, in the same direction, in the same window
• Linked accounts sharing common beneficial ownership, venue, or execution timing
• Coordination frequency inconsistent with independent trading decisions

Reversal After Close

• Price move largely unwinds once the manipulative window closes
• Reversal timing tightly coupled to the account's own exit, not to any market news
• Reversal magnitude disproportionate to the size of the original move

Investigation actions

1. Resolve the account holder, the ultimate owner and the venue.
2. Compute the price impact ratio (price move % / normal volatility %).
3. Compute the volume concentration (account share of total market volume in the window).
4. Count the linked accounts trading in concert with this account.
5. Compute the reversal-after-close ratio (post-period reversal % / price move %).
6. Score each of the four components against its band cut-lines.
7. Aggregate the weighted exposure score; escalate at or above the threshold.

Related typologies

Curated from fc-07-capital-markets-analytics-toolkit/typologies/CM002_Market_Manipulation.md