From FIXwiki

FIX Data Type Price

Name	BaseType	First introduced	Deprecated
Price	float	FIX.4.2

float field representing a price. Note the number of decimal places may vary. For certain asset classes prices may be negative values. For example, prices for options strategies can be negative under certain market conditions. Refer to Volume 7: FIX Usage by Product for asset classes that support negative price values.

Notes

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