How to write in jsx "Not equal"?

i need check, if bleeds have same value:

with (app.activedocument.documentpreferences){

if (documentbleedbottomoffset==documentbleedtopoffset==documentbleedinsideorleftoffset==docu mentbleedoutsideorrightoffset){

alert ("make bleeds equal!"); exit()

}}

but if try:

if (!documentbleedbottomoffset==documentbleedtopoffset==documentbleedinsideorleftoffset==doc umentbleedoutsideorrightoffset){

nothing changes: line "alert" executes anyway. why?

'me' != 'you' //-> true

edit:

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