Definition
The risk arising when a portfolio has excessive exposure to a single counterparty, sector, issuer, or geography, such that losses in that one concentrated position can severely impact overall portfolio performance because returns within the concentrated exposure are correlated rather than diversified.
In Panel Profits
In a comic portfolio, concentration risk arises when a collector or fund holds a disproportionate share of total portfolio value in a single character, publisher, era, or franchise-dependent catalyst set — so that a single bad outcome (a shelved adaptation, a publisher-wide print-quality scandal, or a single character's fall from cultural relevance) can impair a large fraction of total portfolio FMV at once.
Comic-market example
A portfolio where 60% of total verified FMV sits in keys tied to a single franchise's adaptation pipeline carries high concentration risk: if that franchise's adaptation is shelved (see Development Hell), the resulting catalyst decay hits the large majority of the portfolio simultaneously, unlike a portfolio spread across multiple uncorrelated franchises and eras.
Calculation
Concentration Ratio = Value of Largest Single Exposure (issuer / character / franchise) / Total Portfolio Value
Common mistakes
Do not assume owning many different issues automatically means low concentration risk — if those issues all depend on the same underlying catalyst (one franchise, one publisher, one adaptation), the exposure is still concentrated. Do not confuse the number of distinct assets held with genuine diversification of underlying risk drivers.