How are damage reductions from Lich and Jewel calculated?

When I have Lich with Eternal Life, it's assumed that Heavy Buffers 5% + Soulless Forms 10% + Atziris Disdains 10% add up to 25%, rather than working multiplicatively (0.95 x 0.9 x 0.9 = 23% less damage taken).

Does this mean that when I add 8% damage taken from Mana before Life, it adds up to 25+8=33% less damage taken, rather than the 8% applying to the 75% (0.75 x 0.92 = 31% less damage taken)?