Merger control regimes use jurisdictional thresholds to determine whether a transaction must be notified or may otherwise be reviewed (see MJ merger grid—jurisdiction). Turnover thresholds are commonly used, although some regimes use asset, market share, transaction value or other jurisdictional tests, either instead of or in addition to turnover. Calculating and geographically allocating turnover correctly is therefore crucial. Depending on the jurisdiction, failure to notify or comply with an applicable standstill obligation may result in financial or criminal penalties, restorative measures, or the transaction being unwound, declared void or otherwise ineffective. Note—the checklist below summarises Article 5 of the EU Merger Regulation and the Commission Consolidated Jurisdictional Notice. Other jurisdictions may calculate turnover differently. Always check the relevant local rules. Turnover—checklist Key factors to consider when calculating turnover are as follows: • Identify the undertakings concerned—before calculating turnover, identify the undertakings concerned. In an acquisition of sole control, these will generally be the acquiring undertaking and the target undertaking or acquired business; the seller’s retained business is excluded. In a merger, each of the merging undertakings is an undertaking concerned.