Shahrood University of Technology Journal of Algebraic Systems 2345-5128 14 2 2026 04 01 K-bi-g-frames in Hilbert spaces 297 315 3738 10.22044/jas.2024.14492.1834 EN Mohamed Rossafi Laboratory Analysis, Geometry and Applications, Higher School of Education and Training, University Ibn Tofail, Kenitra, Morocco. Abdelilah Karara Laboratory Analysis, Geometry and Applications, Department of Mathematics, University Ibn Tofail, Kenitra, Morocco. Journal Article 2024 05 06 The notion of K-frames generalizes ordinary frames in that the lower frame bound applies only to elements within the range of K. This paper will introduce the new concept of K-bi-g-frames for Hilbert spaces. Then, we examine some characterizations with the help of a biframe operator. Finally, we investigate several results about the stability of K-bi-g-frames produced using frame theory methods. Frame K-frame biframe K-bi-g-frames Hilbert spaces https://jas.shahroodut.ac.ir/article_3738_840512308b3e834d9c52e9cc1a1714ee.pdf