The Local Synchronizing Merge (workflow pattern 7) is the simpler sibling of the general synchronizing merge: the branches to be synchronised were activated by an inclusive split in the same structured block (no loops feeding back, no other splits involved), so the merge can decide locally how many tokens to expect - exactly what a BPMN inclusive gateway pair does.
In IBM BPM / BAW: model a diverging inclusive gateway (OR) with one condition per branch, and a converging inclusive gateway where the branches meet; the engine remembers which branches the split activated and the join waits for those and only those. Implicit joins (several flows into an activity) do not synchronise - they start the activity once per arriving token - so always add the gateway.
BPD "New customer":
(OR gateway "Required checks")
condition "needs KYC": -> [KYC review] --\
condition "amount > 10000": -> [Credit assessment] ---> (OR gateway, converging) -> [Open account]
default: -> [Register only] --/
with KYC and credit both true: [Open account] runs once after both; with neither: after [Register only]Pitfalls: a branch that ends in an end event instead of reaching the join is fine (the token is consumed, the join no longer waits for it); a timer boundary that leaves a branch through another path must also lead to the join, or the join waits forever - operations then sees a "stuck" instance whose only remedy is move token. If the number of parallel branches is data-driven (one per line item), use a multi-instance activity instead.
References