Let's leapfrog to the details behind this remarkable rarity. As described by his owner above, he was indeed produced between 1903 and 1908. Because he does not have ears, his treasured and earliest elephant button is located in his red shorts. Today's example is missing three design elements. His elaborate finger digits, which originally appeared like "lollipops," have been lost to time. He also had long, thin feet, which according to a few photos, could have been designed as simple athletic shoes. He also left the factory in Giengen holding an oar, suggesting he was designed to be a rower or a member of a crew team. When he was new, he appeared as the photo on the left, which is from Pfeiffer's 1892-1943 Sortiment. This hoppy-go-lucky fellow has enormous historical relevance, and could be the topic of a several hour talk all unto himself. However, there are two really, really cool things about him that confirm his gold medal status.
The first is his "doll like" form. Given his anthropomorphic (i.e., sharing human characteristics) presentation, including his standing body position, red shorts, probable shoes, and oar accessory, it is Steiffgal's best guess that he was made as part of Steiff's earliest and little-known all cloth doll line. In 1903, Richard Steiff designed and produced a series of soft cloth play dolls designed to replace the company's somewhat generic bisque-headed dolls. This new line, as far as Steiffgal has been able to research, was entirely, or almost entirely, consisted of only male dolls, including soccer players, policemen, farmers, military personnel, natives, and early cartoon characters. This appears to be the only "animal doll" produced as part of this series. It is exciting to think that Richard Steiff himself may have made this frog doll! An advertising photo of this early collection is pictured above; this illustration is from the Cieslik's Button in Ear book. 
Things also line up with this frog's form relative to other dolls being produced at the time. Here on the left you can see a photo of another early Steiff doll; he is called "Negro" and appeared in the line from 1903-1904. This doll is 35 cm, string jointed, and was made in either velvet or felt. His face comes alive with a prominent center seam, black button eyes framed by embroidery, and a hand embroidered mouth. Steiffgal does not think that it is a coincidence that both the frog doll under discussion and this doll are wearing very similar red shorts with a white tie around the waist, and share many of the same proportions. The photo of the black velvet doll is from the collection of Nancy Smith. 
The second important and key element to this frog doll is "the company he keeps." This frog appears in a 1903/04 catalog photograph used to debut the company's new editions at the annual Leipzig Spring Fair, along with the "Negro" doll and other masculine themed string jointed dolls. But what's so special about that? It's the same picture that debuted PB55... the world's first jointed Teddy bear. Talk about being at the right place at the right time, eh? A snapshot of this catalog page is shown here on the left; you can spot the frog with the oar in the very far right of the picture. You can also click on the photo to make it larger. According to the hand written notes on the photo, these frog dolls were 21 Deutchmark per twelve. This picture is from the Cieslik's Button in Ear book.
Steiffgal hopes this discussion on this early and athletic frog doll has got your pulse racing!