Do bidendates occupy cis position always?

https://chem.libretexts.org/Core/Inorganic_Chemistry/Coordination_Chemistry/Properties_of_Coordination_Compounds/Isomers/Stereoisomers%3A_Geometric_Isomers_in_Transition_Metal_Complexes

In example 1.1, it is written that en which occupy only adjacent positions.....is it true for any bidendate for octahedral isomer?

• It surely depends on the size of the specific ligand. Big floppy ligands might well be able to occupy opposite positions. – matt_black Dec 12 '17 at 15:26

It seems octahedral ones are even rarer than their square planar counterparts, but there has been at least one reported synthesis of a trans-spanned octahedral$^1$ that I could find. In the linked paper, they report the synthesis of trans-$\ce{[Ru(Cl)(trpy)(C3SPAN)]}$ where trpy = 2,2:6,2-terpyridine and C3SPAN=$\ce{Ph2PC6H4CH2O(CO)(CH2)3(CO)OC6H4PPh2}$.
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