Aaron ben Moses ben-Asher (Ben Asher, Abu Sa'id in Arabic, first half of tenth century) was the last and most important of a family of masoretes active in Tiberias for six (or five) generations, from the second half of the eighth century. That Ben-Asher lived in the first half of the tenth century may be deduced from a list in the Keter, a biblical manuscript formerly in Aleppo, now in Israel. This states that Ben-Asher vocalized and masar (i.e., wrote the Masorah of) the Keter, which was written by Solomon b. Bouya'a, a well-known scribe, who wrote another Bible dated 930. It is also known that Ben-Asher was no longer alive in 989, since the scribe of the manuscript of the Former Prophets from that date says of him: "may he rest in the Garden of Eden" (Leningrad, Firkovich II, Ms. 39). Ben-Asher was apparently an elder contemporary of Saadiah Gaon, who wrote the anti-Karaitic critique "Essa Meshali," against Ben-Asher.

Ben-Asher rapidly gained fame as the most authoritative of the Tiberias masoretes, and in 989, the scribe of the above-mentioned manuscript of the Former Prophets vouched for the care with which his copy was written by the fact that he had vocalized and added the masorah "from the books that were [vocalized] by Aaron ben Moses Ben-Asher." Maimonides, by accepting the views of Ben-Asher (though only in regard to open and closed sections), helped establish and spread his authority. Referring to a Bible manuscript then in Egypt, he writes: "All relied on it, since it was corrected by Ben-Asher and was worked on (ve-dikdek bo) by him for many years, and was proofread many times in accordance with the masorah, and I based myself on this manuscript in the Sefer Torah that I wrote" (Yad, Maim. Sefer Torah, 8:4). It is generally agreed that the codex used by Maimonides is that formerly in Aleppo.

The tradition of Ben-Asher is the one accepted in the Jewish Bible, but this does not mean that the version of the Bible found in the common editions is exactly the same as that which Ben-Asher produced. The differences between the printed editions and the various manuscripts assumed to be written in the Ben-Asher tradition are mainly in the placing of the accents, especially the use of the meteg, different uses of the sheva and hataf in certain grammatical forms, all differences that are unimportant for the average reader. These differences developed over the years, usually as a result of grammatical assumptions that were not always correct. Furthermore, certain divergences in vocalization and masorah are found even in manuscripts that are accepted as Ben-Asher codices. This fact, combined with the evidence of Mishael b. Uzziel in his Kitab al-Khulaf, indicates that Ben-Asher used different systems of vocalization at different times in specific words. It may be said, therefore, that different Ben-Asher manuscripts reveal a continual development in his method of vocalization.

Ben-Asher was one of the first to lay the foundations of Hebrew grammar. His Sefer Dikdukei ha-Te'amim (or the Mahberet Ben-Asher, as David Kimhi called it in his commentary on Judg. 6:19) is a collection of grammatical rules and masoretic information. Grammatical principles were not at that time considered worthy of independent study. The value of this work is that the grammatical rules presented by Ben-Asher reveal the linguistic background of vocalization. The book was first published in the Mikra'ot Gedolot (1516–18), and again in 1879 by S. I. Baer and Strack, who edited the material according to topics, in a manner different from that in the first edition. Until recently all studies relating to Ben-Asher's system of grammar and masorah were based on this edition. A. Dotan's edition (1967), which includes a commentary and studies on the content of the book, changed the previous conception of Dikdukei ha-Te'amim as it had been understood for 90 years. Many of the phonological and morphological topics which had been commonly attributed to Dikdukei ha-Te'amim are not included. The main theme discussed in the book is the relationship of the biblical accents to the rules of vocalization and pronunciation. The sheva and its pronunciation play a major part in this work.

Except for certain parts, including masoretic lists, the book is written in a rhymed poetic style, using paytanic language. It can be assumed that the parts not written in this style were not by Ben-Asher. The language of the book shows a certain Arabic influence, particularly with regard to grammatical terms. Even in its more limited form Dikdukei ha-Te'amim is important not only for showing how the different vocalizers determined the correct vocalization, but also for a clearer understanding of the grammatical world of the later masoretes, who laid the foundations for Hebrew grammar in later generations.

Seligman Isaac Baer (1825–1897) was a Hebrew grammarian, masorah scholar, and liturgist. He was a pupil of Wolf Heidenheim, who left him many of his manuscripts. At the age of 19 he turned to masoretic studies. Hermann Leberecht Strack, (1848–1922) was a German orientalist and theologian. He was recognized as a leading non-Jewish scholar in the field of Bible and Talmud, Hebrew and Aramaic linguistics, Masorah, etc. Serving as an expert in German courts on a number of cases with anti-Semitic overtones, Strack took a firm line in defense of Judaism, and at the same time was active in the Protestant missionary movement.