"necessitate obtaining" is a grammatically correct and commonly used phrase in written English.
It means that something requires or demands the action of obtaining something else. Example: The new job position will necessitate obtaining a valid work permit for international employees.
The base squadron faced another challenge in January 1952, following a controversial change in role for the Meteors, from air-to-air combat to ground attack, which necessitated obtaining supplies of rockets and modification of the aircraft to carry them.
In order to take the lubrication advantage of nanographite to water-based fluid, surface modification is necessitated to obtain water-soluble nanographite.
The complexity of the syndrome necessitates data obtained from large epidemiological studies to better understand the factors that facilitate early identification of patients at risk for progressing further along the disease spectrum.
These understood and frequently applied rules for obtaining power necessitate that regardless of whether or not one begins down a path toward power with a certain amount of innocence, by repeating these acts they will -- if they are to truly succeed -- unleash their animal soul.
Therefore, generalizing the health risk from exposure to different fuel sources under a single umbrella term may not be very representative, and may necessitate the need for obtaining region specific estimates.
Even where the mode of obtaining food necessitates solitude and therefore dispersal, there is a tendency for reassembly at the end of the day which is followed by a flight in formation to a communal roost.
Our method of obtaining SF necessitated penetration of the articular space using an 18-gauge needle, a process with obligatory passage through skin and subcutaneous tissue.
The sentence $\forall x \exists y \ x = y$ is of course a theorem of the weaker quantificational logic, but once we necessitate, we only obtain the harmless $\Box \forall x \exists y \ x = y$.
More generally, the obtaining of a fact necessitates the existence of its constituents even though the fact and its constituents are entirely distinct.
Obtaining a maximal score necessitated lots of missing data, coded as Ns, and produced the only datamatrix with no overlap of non-ambiguous data between some taxa.
