Section 5327 of Act 112 deals with "presumptions".
Section 5327 (a) states that, between parents, "there shall be no presumption that custody should be awarded to a particular parent". This is not a change from current law.
Prior to passage of Act 112, there was much speculation that the new law would make shared custody a "rebuttable presumption". In other words, it was thought that the court might be required to order shared custody unless there was a very good reason to do otherwise. But there is no "shared custody presumption" in Act 112. This is one of the reasons we consider the new law to be evolutionary rather than revolutionary.
Under Section 5327 (a) there are no presumptions between parents. In contrast, Section 5327 (b) states that a parent has a rebuttable presumption of winning primary physical custody against a non-parent. This "rebuttable presumption" means that a parent will win a custody battle for primary physical custody against a non-parent, unless there is a very good reason to do otherwise. The exact standard the non-parent must meet is "clear and convincing evidence" that the child would benefit from being in the primary physical custody of the non-parent.
Section 5327 (c) add that there are no presumptions between non-parent "third parties". So, for example, an Aunt would have no presumptions over a cousin or friend.