On the heels of a rash of tech IPOs and multibillion-dollar valuations of soon-to-be public companies, CNBC's Jim Cramer warned investors of "bubbling" throughout areas such as cloud computing, organic food and 3-D printing.
"In other words, there's bubbling everywhere, and it does worry me," Cramer said Friday on "Squawk on the Street." "We saw too much cloud. We saw too much organic food. And now I think we're getting too much of a whole set of areas."
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Cramer cited niche companies such as Violin Memory, a flash storage device maker, and Voxeljet, which manufactures 3-D printers. Both stocks have fallen sharply since their companies recently went public.
"So yes, we need to be careful," Cramer said.
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