What is the rule as regards the joint or solidary character of an obligation?

General Rule:

When two or more creditors or two or more debtors concur in one and the same obligation, the presumption is that the obligation is joint.

Exceptions:

The obligation shall be solidary when:

1. Expressly stipulated that there is solidarity;

2. Law requires solidarity;

3. Nature of the obligation requires solidarity;

4. Charge or condition is imposed upon heirs or legatees and the will expressly makes the charge or condition in solidum (Manresa); or

5. solidary responsibility is imputed by a final Judgment upon several defendants.(Gutierrez v. Gutierrez, 56 Phil 177)