Canon 948 states that ordinarily there may be no more than one offering (intention) for one Mass. However, in 1991 the Congregation for the Clergy issued a decree …Collective Intentions…which permitted the practice of taking more than one offering for a single Mass.
The principle rules governing this practice are:
- The donors must be informed and agree to combine their offerings with others in a single Mass
- The time and place for the celebration of the Mass are to be made public
- Masses for collective intentions may not be celebrated by a priest more than twice a week
- If the total amount of the offerings given for a collective intention exceeds the amount of the usual offering the excess is to be given to the Ordinary for the purposes he has specified.